Answer:
Step-by-step explanation:
a) The sample space, n(S) = 6^6 = 46656
Let the number fair dice toss that show 6 = n(A)
Hence, the probability of getting, P(A) = n(A)/n(S)
b) Sample space, n(S) = 6^42
n(A) = 6^9
∴ P(A) = n(A)/n(S) = 6^9/6^42 = 1/(6^33) = 2.09 X 10^(-26)
c) No
Using only four 4's and any operational sign find the value of 8
Answer:
The answer is 4 + 4 + 4 - 4 = 8
Step-by-step explanation:
The four fours problem is one of the problems given in the book "The Man Who Calculated" by Malba Tahan, a Brazilian-born professor of mathematical sciences.
There are many complicated problems in this book made with the intention of using logic to find a value.
The 4 fours problem is based on using these numbers and using any operation to result in the numbers 1 through 10.
The average price of a college math textbook is $158 and the standard deviation is $26. Suppose that 40 textbooks are randomly chosen. Round all answers to 4 decimal places where possible.
What is the distribution of ¯xx¯? ¯xx¯ ~ N(,)
For the group of 48, find the probability that the average price is between $153 and $155.
Find the first quartile for the average textbook price for this sample size. $ (round to the nearest cent)
For part b), is the assumption that the distribution is normal necessary? Yes No
Please only answer if you are able to answer correctly and entirely.
The probability that the average price is between $153 and $155 is 0.04.
What is the probability?Probability refers to a possibility that deals with the occurrence of random events.
The probability of all the events occurring need to be 1.
The average price of a math textbook =$158
The standard deviation =$26
The mean= 158
n =number of textbooks randomly chosen which is 40
n=10
Then
σ = 26
σₓ = σₓ/√n
= 26/√40
Therefore. σₓ² = 16.90
For the group of 48, find the probability that the average price is between $153 and $155.
The probability that the average price is between $153 and $155
= 0.04
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find the derivative by using product rule and distribution
pls help quickly and show work
Answer:
Below
Step-by-step explanation:
First method:
● f(x)= (x^3-2x+1)×(x-3)
● f'(x)= (x^3-2x+1)' ×(x-3) + (x^3-2x+1)×(x-3)'
●f'(x)= (3x^2-2)×(x-3) + (x^3-2x+1) × 1
●f'(x) = 3x^3-9x^2-2x+6 + x^3-2x+1
● f'(x)= 4x^3-9x^2-4x+7
■■■■■■■■■■■■■■■■■■■■■■■■■■
Second method:
●f(x) = (x^3-2x+1)×(x-3)
●f(x) = x^4-3x^3 -2x^2+6x+x-3
●f(x) = x^4-3x^3-2x^2+7x-3
●f'(x) = 4x^3-9x^2-4x+7
We got the same result using both methods.
what does 7g equal in like a verbal form
Answer:
see below
Step-by-step explanation:
7g can be "split" as 7 * g. The "*" means multiplication so a verbal form of this expression could be "7 times a number g" or "The product of 7 and a number g".
The letters x and y represent rectangular coordinates. Write the given equation using polar coordinates (r,θ) . Select the correct equation in polar coordinates below.
x2+y2−4x=0
a. r=4 sinθ
b. r=4 cosθ
c. r cos2θ=4 sinθ
d. r sin2θ=4 cosθ
Answer:
B. r = 4cosθStep-by-step explanation:
Given the expression in rectangular coordinate as x²+y²−4x=0, in order to write the given expression in polar coordinates, we need to write the value of x and y as a function of (r, θ).
x = rcosθ and y = rsinθ.
Substituting the value of x and y in their polar form into the given expression we have;
x²+y²−4x=0
( rcosθ)²+( rsinθ)²-4( rcosθ) = 0
Expand the expressions in parenthesis
r²cos²θ+r²sin²θ-4rcosθ = 0
r²(cos²θ+sin²θ)-4rcosθ = 0
From trigonometry identity, cos²θ+sin²θ =1
The resulting equation becomes;
r²(1)-4rcosθ = 0
r²-4rcosθ = 0
Add 4rcosθ to both sides of the equation
r²-4rcosθ+4rcosθ = 0+4rcosθ
r² = 4rcosθ
Dividing both sides by r
r²/r = 4rcosθ/r
r = 4cosθ
Hence the correct equation in polar coordinates is r = 4cosθ
PLEASE HELP IM SO LOST
1. Ted is working on his financial plan and lists all of his income and expenses in the spreadsheet below.
А
B
Net Pay
$5,000
2
Interest on Deposits $0
3 Income from Investments $225
4 Rent
$3,000
5 Utilities
$250
6 Satellite Dish
$175
7 Cell Phone Plan
$135
8 Car Payment
$385
9 Groceries
$200
10 Insurance
$380
11 Recreation
$400
What is Ted's net cash flow?
2. Tamara earns $8 an hour at her job working 25 hours per week. If her net pay is 78% of her paycheck
and she has no other sources of income, what is Tamara's monthly cash inflow? (Assume there are 4
pays per month.)
Answer: 1) $300 2) $624
Step-by-step explanation:
[tex]\begin{array}{l||l|l}\underline{\quad \text{Item}\qquad \qquad \qquad \qquad}&\underline{\text{Income} }&\underline{\text{Expense}}\\\text{Net Pay}&5000&\\\text{Interest on Deposits}&0&\\\text{Income from Investments}&225&\\\text{Rent}&&3000\\\text{Utilities}&&250\\\text{Satellite Dish}&&175\\\text{Cell Phone Plan}&&135\\\text{Car Payment}&&385\\\text{Groceries}&&200\\\text{Insurance}&&380\\\underline{\text{Recreation}\qquad \qquad \qquad}&\underline{\qquad \quad }&\underline{400\qquad}\\\end{array}[/tex]
TOTALS 5225 4925
Net Cash Flow = Income - Expenses
= 5225 - 4925
= 300
*************************************************************************************
[tex]\dfrac{25\ hours}{week}\times \dfrac{\$8}{hour}\times 4\ weeks\times 78\%\\\\\\=25\times \$8 \times 0.78\\\\= \$624[/tex]
On a class trip with 40 students, 14 are male. What percentage of the class is female?
66%
60%
65%
58%
Answer:
65%
Step-by-step explanation:
If 14 are male, then 26 are female.
To find the percent female, divide the number of females by the total.
26/40 = 0.65
So, the percentage of the class that is female is 65%
Answer:
C. 65%
Step-by-step explanation:
We know that of the 40 total students, 14 are male, which means the remaining students are female.
To find how many are female, we subtract 14 from 40:
40 - 14 = 26 females
Percentage is simply a part divided by a whole, multiplied by 100. Here, the "part" is the number of females, which is 26. The "whole" is the total number of students, which is 40. So, we have:
(26 / 40) * 100 = 65
The answer is thus C, 65%.
~ an aesthetics lover
Find the area of the triangle.
[? ] ft2
Don't round
Step-by-step explanation:
[tex]Area = \: \frac{bh}{2} \\ : b = 16.9 \: h = 10.4 \\ [/tex]
[tex]Area = \frac{16.9 \times 10.4}{2} = \frac{175.76}{2} = 87.88 {ft}^{2} [/tex]
Base = 16.9
height = 10.4
Area = ½b×h
A = ½(16.9×10.4)
A = ½(175.76)
Area = 175.76/2
A = 87.88ft²
Answer:
[tex]\Large \boxed{\mathrm{87.88 \ ft^2 }}[/tex]
Step-by-step explanation:
[tex]\displaystyle area \ of \ triangle \ = \ \frac{base \times height }{2}[/tex]
[tex]\displaystyle area \ of \ triangle \ = \ \frac{16.9 \times 10.4 }{2}[/tex]
[tex]\displaystyle area \ of \ triangle \ = \ \frac{175.76}{2}[/tex]
[tex]\displaystyle area \ of \ triangle \ = \ 87.88[/tex]
I really need help i will rate you branliest
Work Shown:
A = P*(1+r)^t
A = 21450*(1+(-0.08))^5
A = 21450*(1-0.08)^5
A = 21450*(0.92)^5
A = 21450*0.6590815232
A = 14137.29867264
A = 14,137.30
Notice how I used a negative r value to indicate depreciation rather than growth.
A young sumo wrestler decided to go on a special high-protein diet to gain weight rapidly. When he started his diet, he weighed 79.5 kilograms. He gained weight at a rate of 5.5 kilograms per month. Let y represent the sumo wrestler's weight (in kilograms) after x months. Which of the following could be the graph of the relationship? graph of an increasing linear function in quadrant 1 with a positive y-intercept (Choice B) B graph of an increasing linear function in quadrants 1 and 4 with a positive x-intercept and negative y-intercept (Choice C) C graph of a decreasing linear function in quadrants 1 and 4 with a positive x-intercept and positive y-intercept (Choice D) D graph of a decreasing linear function in quadrant 4 with a negative y-intercept
Answer:
(Choice A) A graph of an increasing linear function in quadrant 1 with a positive y-intercept.
Step-by-step explanation:
The weight of the sumo wrestler starts at a positive value of 79.5 kilograms, and we are given that the sumo wrestler gains a linear amount of weight per month at 5.5 kilograms per month.
If we were to graph this relationship, the sumo wrestler's weight would be represented on the y-axis, and the amount of time on the x-axis.
So the initial weight would occur at (0, 79.5) which is the positive y-intercept.
And since his weight is increasing at 5.5 kilograms per month, the slope of the linear function is positive.
Hence, the graph of the linear increasing function in quadrant 1 with a positive y-intercept.
Cheers.
ASAP
Which of the following factors determine a plane? A. line and a point on the line B. two lines C. a straight line D. a line and a point not on that line
Answer:
D. a line and a point not on that line
Step-by-step explanation:
That is how you determine a plane.
The factors which determine a plane are a line and a point not on that line.
What is plane ?
In geometry, a plane is a flat surface that extends into infinity.
In a three dimensional space, a plane can be defined by three points it contains, as long as those points are not on the same line.
Therefore, the factors which determine a plane are a line and a point not on that line.
Hence, option D is correct.
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Your friend Iggy tells you that the product of 80 and 70 will have four zeroes. Explain to Iggy why his estimation is incorrect, and how to fix it.
4 zeroes basically means [tex]10^4[/tex]
$80=2^3\cdot 10$ and $70=7\cdot10$
there will be $10^2$ when you take the product not $10^4$
hence it will have 2 zeroes not 4
the coefficient of 6x
Answer:
The coefficient is 6
Step-by-step explanation:
The coefficient is the number in front of the variable
The variable is x
The coefficient is 6
Answer:
6
Step-by-step explanation: The coefficient of this would be the real number that is in front of a variable that is not a variable like x, and that number is 6. So, the coefficient of 6x is 6.
Given the two functions, which statement is true?
fx = 3^4, g(x) = 3^x + 5
Answer:
third option
Step-by-step explanation:
Given f(x) then f(x) + c represents a vertical translation of f(x)
• If c > 0 then shift up by c units
• If c < 0 then shift down by c units
Given
g(x) = [tex]3^{x}[/tex] + 5 ← this represents a shift up of 5 units
Thus g(x) is the graph of f(x) translated up by 5 units
Answer:
[tex]\boxed{\sf{Option \: 3}}[/tex]
Step-by-step explanation:
g(x) is translated up 5 units compared to f(x). In a vertical translation, when the graph is moved 5 units up, 5 is added to the function. When the graph is moved 5 units down, 5 is subtracted from the function. The graphs are shifted in the direction of the y-axis.
Based on this plot, which one of the following statements is not correct? The median room rate is $150 per night. There is one outlier in this data set. The 25th percentile in this data set is $130 per night. The second quartile in the data set is $160 per night.
Answer:
The second quartile in the data set is $130 per night.
Step-by-step explanation:
Quartile is a type of quantile which divides the number of data set into even numbered sub groups. The second quartile is median of data set. This means that 5% of data lies within this point. The middle value between the median and highest value of data set. The second quartile in the data set must be 50% so the statement is not correct.
-x + 3y = 3
x - 3y = 3
Does this system have a solution?
Answer:
No solution
Step-by-step explanation:
Slope-Intercept Form: y = mx + b
Step 1: Write out systems of equations
-x + 3y = 3
x - 3y = 3
Step 2: Rewrite equations into slope-intercept form
3y = 3 + x
y = 1 + x/3
-3y = 3 - x
y = -1 + x/3
Step 3: Rewrite systems of equations
y = x/3 + 1
y = x/3 - 1
Since we have the same slope for both equations but different y-intercepts, we know that both lines are parallel. If that is the case, they will never touch or intersect each other. Therefore, we have no solution.
(a) A survey of the adults in a town shows that 8% have liver problems. Of these, it is also found that 25% are heavy drinkers, 35% are social drinkers and 40% are non-drinkers. Of those that did not suffer from liver problems, 5% are heavy drinkers, 65% are social drinkers and 30% do not drink at all. An adult is chosen at random, what is the probability that this person i. Has a liver problems?
Answer:
The probability that the selected adult has liver problems is 0.08
Step-by-step explanation:
In this question, from the data given, we want to calculate the probability that an adult selected at random has liver problems.
Let E(L) be the event that an adult has liver problems.
The probability is directly obtainable from the question and it is given as 8%
Thus, the probability that the selected adult has liver problems; P(L) = 8% = 8/100 = 0.08
Sugar, flour, and oats are stored in three drawers. The first drawer is labeled "oats", the second is labeled, "flour", the third is labeled "oats or flour". The label of each drawer does not correspond to what is stored inside of it. In which drawers is what stored?
Answer:
first = flour, second = oats, third = sugar
Step-by-step explanation:
Since the labels are "wrong", we know that the third drawer doesn't have oats or flour, therefore it has sugar. Since the first doesn't have oats, it must have flour and that makes the second drawer oats.
Answer:
first drawer has flour, second has oats, third is sugar
Step-by-step explanation:
on the first drawer, it is labelled oats, so it cannot be oats. on the second it cannot be flour, and on the third it cannot be oats or flour, which means it HAS to be sugar leaving oats and flour to be in either the first, or second.
i know it may sound a little confusing but please let me know if you dont understand
Two numbers, if the first one increases by 1, and the second one decreases by 1, then their product increases by 2020. If the first number decreases by 1, and the second one increases by 1, what value does the product decrease?
Answer:
The product decreases 2022.
Step-by-step explanation:
(x + 1)(y - 1) = xy + 2020
xy - x + y - 1 = xy + 2020
-x + y = 2021
(x - 1)(y + 1) = xy + x - y - 1
+ 2021 = -x + y
----------------------------------
(x - 1)(y + 1) + 2021 = xy - 1
(x - 1)(y + 1) = xy - 2022
The product decreases 2022.
What is the critical F value when the sample size for the numerator is seven and the sample size for the denominator is six
Answer:
Critical F value = 4.9503
Step-by-step explanation:
Given that:
The sample size of the numerator = 7
The sample size of the denominator = 6
The degree of freedom for the numerator df = n -1
The degree of freedom for the numerator df = 7 - 1
The degree of freedom for the numerator df = 6
The degree of freedom for the denominator df = n - 1
The degree of freedom for the denominator df = 6 - 1
The degree of freedom for the denominator df = 5
The assume that the test is two tailed and using a level of significance of ∝ = 0.10
The significance level for the two tailed test = 0.10/2 = 0.05
From the standard normal F table at the level of significance of 0.05
Critical F value = 4.9503
Solve for x. 2x+3≤x−5 x≤−8 x≤2 x≤8 x≤−2
Answer:
x≤−8
Step-by-step explanation:
2x+3≤x−5
Subtract x from each side
2x-x+3≤x-x−5
x+3≤−5
Subtract 3 from each side
x+3-3≤−5-3
x≤−8
Answer:
[tex]\huge \boxed{x \leq -8}[/tex]
Step-by-step explanation:
[tex]2x+3 \leq x-5[/tex]
[tex]\sf Subtract \ x \ from \ both \ parts.[/tex]
[tex]2x+3 -x\leq x-5-x[/tex]
[tex]\sf Simplify \ the \ inequality.[/tex]
[tex]x+3 \leq -5[/tex]
[tex]\sf Subtract \ 3 \ from \ both \ parts.[/tex]
[tex]x+3-3 \leq -5-3[/tex]
[tex]\sf Simplify \ the \ inequality.[/tex]
[tex]x \leq -8[/tex]
On dividing polynomial p(x) by a linear binomial, X - a, we get a quotien
statements must be proven true for the remainder theorem to be true
Answer:
Step-by-step explanation:
Hello, we can write
(1) p(x)=(x-a)q(x)+r
[tex]\boxed{\sf v}[/tex] True
It means that p(a)=0 * q(a) + r = r
so the first one is true.
[tex]\boxed{}[/tex] False
The second one is not to be proven true from the remainder theorem.
[tex]\boxed{\sf v}[/tex] True
For x different from a we can divide the equation (1) by (x-a).
[tex]\boxed{}[/tex] False
We cannot say anything on q(a).
[tex]\boxed{\sf v}[/tex] True
If the rest is 0 then it means that p(a) = 0
[tex]\boxed{\sf v}[/tex] True
If p(a) = 0 it means that the rest r = 0 and then p(x)=q(x)(x-a)
Thank you
Solve the following equation using the square root property.
9x2 + 10 = 5
Use Lagrange multipliers to find three numbers whose sum is 30 and the product P = x3y4z is a maximum. Choose the answer for the smallest of the three values. Question 20 options: a) 21/4 b) 5 c) 15/4 d) 3
We want to maximize [tex]x^3y^4z[/tex] subject to the constraint [tex]x+y+z=30[/tex].
The Lagrangian is
[tex]L(x,y,z,\lambda)=x^3y^4z-\lambda(x+y+z-30)[/tex]
with critical points where the derivatives vanish:
[tex]L_x=3x^2y^4z-\lambda=0[/tex]
[tex]L_y=4x^3y^3z-\lambda=0[/tex]
[tex]L_z=x^3y^4-\lambda=0[/tex]
[tex]L_\lambda=x+y+z-30=0[/tex]
[tex]\implies\lambda=3x^2y^4z=4x^3y^3z=x^3y^4[/tex]
We have
[tex]3x^2y^4z-4x^3y^3z=x^2y^3z(3y-4x)=0\implies\begin{cases}x=0,\text{ or}\\y=0,\text{ or}\\z=0,\text{ or}\\3y=4x\end{cases}[/tex]
[tex]3x^2y^4z-x^3y^4=x^2y^4(3z-x)=0\implies\begin{cases}x=0,\text{ or}\\y=0,\text{ or}\\3z=x\end{cases}[/tex]
[tex]4x^3y^3z-x^3y^4=x^3y^3(4z-y)=0\implies\begin{cases}x=0,\text{ or}\\y=0,\text{ or}4z=y\end{cases}[/tex]
Let's work with [tex]x=3z[/tex] and [tex]y=4z[/tex], for which we have
[tex]x+y+z=8z=30\implies z=\dfrac{15}4\implies\begin{cases}x=\frac{45}4\\y=15\end{cases}[/tex]
The smallest of these is C. 15/4.
Please help me with this question
Answer:
0 ≤ x ≤ 10
Step-by-step explanation:
The domain of f(x) is the set of values of x for which the function is defined. Here, the square root function is only defined for non-negative arguments, so we require ...
-x^2 +10x ≥ 0
x(10 -x) ≥ 0
The two factors in this product will both be positive only for values ...
0 ≤ x ≤ 10 . . . . the domain of f(x)
According to a study, the probability that a randomly selected teenagar shopped at a mall at least once during a week was 0.61. Let X be the number of students in a randomly selected group of 50 that will shop at a mall during the next week. (a) Compute the expected value and standard deviation of X. expected value standard deviation (b) Fill in the missing quantity. (Round your answer to the nearest whole number.)There is an approximately 2.5% chance that _____ or more teenagers in the group will shop at the mall during the next week.
Answer:
Step-by-step explanation:
Given that:
p = 0.61
If X is the the number of students in a randomly selected group of a sample size n = 50
The expected value and the standard deviation can be computed as follows:
The expected value E(X) = np
The expected value E(X) = 50 × 0.61
The expected value E(X) = 30.5
The required standard deviation = [tex]\sqrt{np(1-p)}[/tex]
The required standard deviation = [tex]\sqrt{30.5(1-0.61)}[/tex]
The required standard deviation = [tex]\sqrt{30.5(0.39)}[/tex]
The required standard deviation = [tex]\sqrt{11.895}[/tex]
The required standard deviation = 3.4489
The required standard deviation = 3.45
(b) Fill in the missing quantity. (Round your answer to the nearest whole number.)
There is an approximately 2.5% chance that _____ or more teenagers in the group will shop at the mall during the next week.
From the given information:
Now, we can deduce that:
the mean = 30.5
standard deviation = 3.45
Using the empirical rule:
At 95% confidence interval;
[μ - 2σ, μ + 2σ] = [ 30.5 - 2(3.45) , 30.5 + 2(3.45)]
[μ - 2σ, μ + 2σ] = [ 30.5 - 6.9 , 30.5 + 6.9]
[μ - 2σ, μ + 2σ] = [ 23.6, 37.4]
The 2.5% of the observations are less than 95% confidence interval and 2.5% observations are greater than 95% confidence interval.
The required number of teenagers is = the upper limit of the 95% confidence interval = 37
There is an approximately 2.5% chance that __37___ or more teenagers in the group will shop at the mall during the next week.
Give this problem a try and try to solve this
Answer:
No solution
Step-by-step explanation:
Given equation is,
[tex]\frac{x^{\frac{1}{2}}+x^{-\frac{1}{2}}}{1-x}+\frac{1-x^{-\frac{1}{2}}}{1+x^\frac{1}{2}}-\frac{(4+x)^\frac{1}{2}}{(1-x)^\frac{1}{2}}=0[/tex]
[tex]\frac{x^{\frac{1}{2}}+x^{-\frac{1}{2}}}{1-x}+\frac{1-x^{-\frac{1}{2}}}{1+x^\frac{1}{2}}=\frac{(4+x)^\frac{1}{2}}{(1-x)^\frac{1}{2}}[/tex]
[tex]\frac{(x+1)}{\sqrt{x}(1-x)}+\frac{(\sqrt{x}-1)}{\sqrt{x}(1+\sqrt{x})}=(\frac{4+x}{1-x})^{\frac{1}{2}}[/tex]
[tex]\frac{(\sqrt{x}+1)(x+1)+(\sqrt{x}-1)(1-x)}{\sqrt{x}(1-x)(1+\sqrt{x})}=(\frac{4+x}{1-x})^{\frac{1}{2}}[/tex]
[tex]\frac{x\sqrt{x}+x+\sqrt{x}+1+\sqrt{x}-1-x\sqrt{x}+x}{\sqrt{x}(1-x)(1+\sqrt{x})}=(\frac{4+x}{1-x})^\frac{1}{2}[/tex]
[tex]\frac{2x+2\sqrt{x}}{\sqrt{x}(1-x)(1+\sqrt{x})}=(\frac{4+x}{1-x})^\frac{1}{2}[/tex]
[tex]\frac{2(\sqrt{x}+1)}{(1-x)(1+\sqrt{x})}=(\frac{4+x}{1-x})^\frac{1}{2}[/tex]
[tex]\frac{2}{1-x}=(\frac{4+x}{1-x})^\frac{1}{2}[/tex] if x ≠ ±1
[tex](\frac{2}{1-x})^2=\frac{4+x}{1-x}[/tex] [Squaring on both the sides of the equation]
[tex]\frac{4}{(1-x)}=(4+x)[/tex]
4 = (1 - x)(4 + x)
4 = 4 - 4x + x - x²
0 = -3x - x²
x² + 3x = 0
x(x + 3) = 0
x = 0, -3
But both the solutions x = 0 and x = -3 are extraneous solutions, given equation has no solution.
Answer:
Could you please help me Genius??????
Twice the difference of a number and 9 is 3. Use the variable b for the unknown number.
Answer:
b = 10.5
Step-by-step explanation:
2(b-9) = 3
then:
2*b + 2*-9 = 3
2b - 18 = 3
2b = 3 + 18
2b = 21
b = 21/2
b = 10.5
check:
2(10.5 - 9) = 3
2*1.5 = 3
Three 3.0 g balls are tied to 80-cm-long threads and hung from a single fixed point. Each of the balls is given the same charge q. At equilibrium, the three balls form an equilateral triangle in a horizontal plane with 20 cm sides. What is q?
Answer:
q = 0.105uC
Step-by-step explanation:
We can determine the force on one ball by assuming two balls are stationary, finding the E field at the lower right vertex and calculate q from that.
Considering the horizontal and vertical components.
First find the directions of the fields at the lower right vertex. From the lower left vertex the field will be at 0° and from the top vertex, the field will be at -60° or 300° because + charge fields point radially outward in all directions. The distances from both charges are the same since this is an equilateral triangle. The fields have the same magnitude:
E=kq/r²
Where r = 20cm
= 20/100
= 0.2m
K = 9.0×10^9
9.0×10^9 × q /0.2²
9.0×10^9/0.04
2.25×10^11 q
These are vector fields of course
Sum the horizontal components
Ecos0 + Ecos300 = E+0.5E
= 1.5E
Sum the vertical components
Esin0 + Esin300 = -E√3/2
Resultant = √3E at -30° or 330°
So the force on q at the lower right corner is q√3×E
The balls have two forces, horizontal = √3×E×q
and vertical = mg, therefore if θ is the angle the string makes with the vertical tanθ = q√3E/mg
mg×tanθ = q√3E.
..1
Then θ will be...
Since the hypotenuse = 80cm
80cm/100
= 0.8m
The distance from the centroid to the lower right vertex is 0.1/cos30 =
0.1/0.866
= 0.1155m
Hence,
0.8×sinθ = 0.1155
Sinθ = 0.1155/0.8
Sin θ = 0.144375
θ = arch sin 0.144375
θ = 8.3°
From equation 1
mg×tanθ = q√3E
g = 9.8m/s^2
m = 3.0g = 0.003kg
0.003×9.8×tan(8.3)
0.00428 = q√3E
0.00428 = q×1.7320×E
Where E=kq/r²
Where r = 0.2m
0.0428 = kq^2/r² × 1.7320
K = 9.0×10^9
0.0428/1.7320 = 9.0×10^9 × q² / 0.2²
0.02471×0.04 = 9.0×10^9 × q²
0.0009884 = 9.0×10^9 × q²
0.0009884/9.0×10^9 = q²
q² = 109822.223
q = √109822.223
q = 0.105uC
What is the solution to this ?
Answer:
[tex]\boxed{\sf C. \ x\geq -4}[/tex]
Step-by-step explanation:
[tex]-8x+4\leq 36[/tex]
[tex]\sf Subtract \ 4 \ from \ both \ sides.[/tex]
[tex]-8x+4-4 \leq 36-4[/tex]
[tex]-8x\leq 32[/tex]
[tex]\sf Divide \ both \ sides \ by \ -8.[/tex]
[tex]\frac{-8x}{-8} \leq \frac{32}{-8}[/tex]
[tex]x\geq -4[/tex]