[tex]\displaystyle f(x)=\sin(3x)\\\\\\f'(x)=\lim_{h\to0}\dfrac{\sin(3(x+h))-\sin(3x)}{h}\\\\f'(x)=\lim_{h\to0}\dfrac{\sin(3x+3h)-\sin(3x)}{h}\\\\f'(x)=\lim_{h\to0}\dfrac{2\cos\left(\dfrac{3x+3h+3x}{2}\right)\sin\left(\dfrac{3x+3h-3x}{2}\right)}{h}\\\\f'(x)=\lim_{h\to0}\dfrac{2\cos\left(\dfrac{6x+3h}{2}\right)\sin\left(\dfrac{3h}{2}\right)}{h}\\\\f'(x)=\lim_{h\to0}\dfrac{2\cos\left(\dfrac{6x+3h}{2}\right)\sin\left(\dfrac{3h}{2}\right)}{\dfrac{3h}{2}}\cdot\dfrac{3}{2}[/tex]
[tex]\displaystyle f'(x)=\lim_{h\to0}2\cos\left(\dfrac{6x+3h}{2}\right)\cdot\dfrac{3}{2}\\\\f'(x)=\lim_{h\to0}3\cos\left(\dfrac{6x+3h}{2}\right)\\\\f'(x)=3\cos\left(\dfrac{6x+3\cdot 0}{2}\right)\\\\f'(x)=3\cos\left(\dfrac{6x}{2}\right)\\\\f'(x)=3\cos(3x)[/tex]
The derivative of sin 3x using first principles is; 3cos(3x)
We want to find the derivative of sin 3x using first principles.
Step 1;
f'(x) = [tex]\lim_{h \to \ 0} \frac{(sin3(x + h)) - sin(3x)}{h}[/tex]
Step 2; Expand the bracket to get;
f'(x) = [tex]\lim_{h \to \ 0} \frac{(sin(3x + 3h)) - sin(3x)}{h}[/tex]
Step 3: According to trigonometric identities, we know that;
sin A - sin B = [tex]2cos\frac{A + B}{2} sin\frac{A - B}{2}[/tex]
Applying that to the answer in step 2 gives;
f'(x) = [tex]\lim_{h \to \ 0} \frac{2(cos\frac{(3x + 3h + 3x)}{2}) sin\frac{(3x + 3h - 3x)}{2})}{h}[/tex]
Step 4; Simplify the brackets to obtain;
f'(x) = [tex]\lim_{h \to \ 0} \frac{2(cos\frac{(6x + 3h)}{2}) sin\frac{(3h)}{2})}{h}[/tex]
Step 5; Rewrite the denominator to get;
f'(x) = [tex]\lim_{h \to \ 0} \frac{2(cos\frac{(6x + 3h)}{2}) sin\frac{(3h)}{2})}{\frac{3h}{2}*\frac{2}{3}}[/tex]
Step 6; Input the limit of 0 for h to get;
f'(x) = [tex]\frac{2(cos\frac{(6x)}{2}) sin\frac{(0)}{2})}{\frac{0}{2}*\frac{2}{3}}[/tex]
⇒ f'(x) = [tex]\frac{2(cos3x)}{2/3} \frac{ 0}{{0}}[/tex]
0/0 = 1. Thus;
f'(x) = 3cos(3x)
Read more about differentiation from first principles at; https://brainly.com/question/5313449
HELP ME IM GONNA CRY PLEASE
A car was purchased for $20,000. The car depreciates by 22% of each year.
a) What is the value of the car when it is 12 years
old?
b) How long will it take for the car to be worth less than $100?
Hello, a car was purchased for $20,000.
This is the initial value.
The car depreciates by 22% of each year.
After 1 year, the value is the initial value 20,000 minus 22% of 20,000.
[tex]20000-20\%*20000=20000\cdot (1-20\%)=20000\cdot (1-0.20)=20000\cdot 0.8=16000[/tex]
After 2 years, the value is.
[tex]20000\cdot 0.8\cdot 0.8=20000\cdot0.8^2=12800[/tex]
Let's take n a positive integer, after n years, the value is.
[tex]\large \boxed{\sf \bf \ 20000\cdot0.8^n \ }[/tex]
a) After 12 years, the value is.
[tex]20000\cdot0.8^{12}=1374.389...[/tex]
This is rounded to $1,374
b) We need to find n such that
[tex]20000\cdot0.8^n=100\\\\ln(20000)+nln(0.8)=ln(100)\\\\n=\dfrac{ln(100)-ln(20000)}{ln(0.8)}=23.74...[/tex]
This is around 23.75 meaning 23 years and 75% of 1 year (meaning 9 months).
So to be worth less than $100, 23 years and 9 months are required.
Thank you
Question 12
1 pts
Whitney recently created a new smartphone app. As a result of the initial costs and
fees of producing the app, she did not make any money, or profit, selling the app during
the first two months of the app's release. For the first month, Whitney had a loss of
$324. During the second month of sales, she had a loss of $97. She hopes that in the
third month, she will sell enough apps to break even-that is, she hopes to earn enough
money to cover her losses. What is the amount of money Whitney needs to make in the
third month in order to break even with app sales so far?
Answer:
The amount (revenue) she makes in the third month to break even is $97
Step-by-step explanation:
The given parameters are;
The cost of the app = Initial cost + fees for producing the app
The amount she loss in the first month = Cost of the app - revenue = $324
The amount she loss in the second month = Loss from first month - revenue in second month = $324 - revenue in second month = $97
The amount Whitney has to make in the third month to break even is therefore;
The amount she makes in the third month to break even is given by the equation;
Revenue from third month - Loss from second month = 0
Which gives;
The amount she makes in the third month to break even is given by Revenue from third month - $97 = 0
∴ Revenue from third month = $97
The amount (revenue) she makes in the third month to break even = $97
The width of a rectangle measures (6.8d-4.2)(6.8d−4.2) centimeters, and its length measures (9.2d+8.7)(9.2d+8.7) centimeters. Which expression represents the perimeter, in centimeters, of the rectangle?
Answer:
The perimeter of the rectangle is represented by [tex]p = 32\cdot d + 9[/tex], measured in centimeters.
Step-by-step explanation:
The perimeter ([tex]p[/tex]) of a rectangle, measured in centimeters, is represented by this formula:
[tex]p = 2\cdot (w+l)[/tex]
Where [tex]w[/tex] and [tex]l[/tex] are width and length, measured in centimeters.
If [tex]w = 6.8\cdot d-4.2[/tex] and [tex]l = 9.2\cdot d+8.7[/tex], the expression that represents the perimeter is:
[tex]p = 2\cdot (16\cdot d +4.5)[/tex]
[tex]p = 32\cdot d + 9[/tex]
The perimeter of the rectangle is represented by [tex]p = 32\cdot d + 9[/tex], measured in centimeters.
Find the distance across the lake. Assume the triangles are similar.
80 m
х
у
20 m
60 m
Answer:
a
Step-by-step explanation:
Answer:
A. L = 240 m
Step-by-step explanation:
use similar triangle
L / 60 = 80 / 20
L = (80 * 60) / 20
L = 240 m
What two numbers multiply to negative 12 and add up to negative 13
Answer:
−13.8654599313 and 0.8654599313
Step-by-step explanation:
The two numbers of interest will be the solutions to ...
xy = -12
x +y = -13
Substituting for y, this becomes the quadratic ...
x(-13 -x) = -12
x^2 +13x = 12 . . . . . multiply by -1
x^2 +13x +6.5^2 = 12 +6.5^2 . . . . . complete the square
(x +6.5)^2 = 54.25
x = -6.5 ± √54.25 . . . . . . take the square root, subtract 6.5
x ≈ -13.865499313 or 0.8654599313
The value of y is the other of these two numbers. So, the two numbers of interest are {-13.865499313, 0.8654599313}.
what is the area of the kite ? PLEASE HELP BEING TIMED
Answer:
7 * 4 / 2 = 28/2 = 14
Step-by-step explanation:
You are timed. I will just give you the formula where its multiplying the Diagonals and dividing by 2.
x= -4 w= 1 z= -3 y= 5
This is the answer!
Solve for X answer asap thanks
Answer:
Step-by-step explanation:
The formula we need for this is
4(4 + x) = 5(5 + 3) and
16 + 4x = 5(8) and
16 + 4x = 40 and
4x = 24 so
x = 6, choice C.
The loudness, L , of a sound (measured in decibels, dB) is inversely proportional to the square of the distance, d , from the source of the sound. When a person 14 feet from a jetski, it is 70 decibels loud. How loud is the jetski when the person is 46 feet away?
Answer:
Loudness (L) = 6.48 dB
Step-by-step explanation:
Given:
Loudness (L) = k / d² , where k = constant
So,
70 = k / 14²
k = 13,720
New distance = 46 feet
Find:
Loudness (L) = ?
Computation:
Loudness (L) = 13,720 / 46²
Loudness (L) = 13,720 / 2,116
Loudness (L) = 6.48 dB
Write the event as set of outcomes. We flip three coins and obtain more tails than heads.
A. {ttt}
B. {ttt, tth, tht, htt}
C. {ttt, tth}
D. {tth, tht, htt}
Answer:
B.
Step-by-step explanation:
All the possible outcomes are listed on choice B.
The event is a set of outcomes. if we flip three coins and obtain more tails than heads is E = {ttt, tth, tht, htt} option (B) is correct.
What is set?A set is a collection of clearly - defined unique items. The term "well-defined" applies to a property that makes it simple to establish whether an entity actually belongs to a set. The term 'unique' denotes that all the objects in a set must be different.
We have three coins.
As we know, in a coin there are two sides head and a tail.
If we flip three coins then the set of all the possible outcomes:
O = {HHH,HHT,HTH,HTT,THH,THT,TTH,TTT}
The set of outcomes has more tails than heads.
E = {ttt, tth, tht, htt}
We can find the probability, the probability can be defined as the ratio of the number of favorable outcomes to the total number of outcomes, in other words, the probability is the number that shows the happening of the event.
Probability = 4/8 = 1/2
Thus, the event is a set of outcomes. if we flip three coins and obtain more tails than heads is E = {ttt, tth, tht, htt} option (B) is correct.
Learn more about the set here:
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Find the value of x. Round to the nearest tenth.Find the value of x. Round to the nearest tenth.
Answer:
x = 55.6Step-by-step explanation:
In order to find the value of x we use sine
sin ∅ = opposite / hypotenuse
From the question
x is the hypotenuse
the opposite is 19
So we have
sin 20 = 19/x
x = 19/sin 20
x = 55.55
We have the final answer as
x = 55.6 to the nearest tenthHope this helps you
Answer:
x = 55.6
Step-by-step explanation:
What is the rate of change and initial value for the linear relation that includes the points shown in the table?
ху
1 20
3 10
5 0
7 -10
Initial value: 20, rate of change: 10
Initial value: 30, rate of change: 10
Initial value: 25, rate of change: -5
Initial value: 20, rate of change: -10
Answer:
Initial Value: 25, Rate of change -5.
First. Lets find the rate of change.
y2-y1/x2-x1 = m
We have A(1,20) B(3,10)
10-20/3-1=-5
m=-5(Rate of change)
Now let's find the initial value using slope-point form.
y-y₁=m(x-x₁)
y-20=-5(x-1)
=-5x+5+20
=-5x+25
The initial value is the value of y when the value of x is equal to 0. (Also the Y-Intercept)
Initial Value = -5(0)+25
=25
How many students in the survey were in the age category of 18 to 22?
Answer:
82
Step-by-step explanation:
78 + 4 = 82
Answer:
82 students
Step-by-step explanation:
The chart has a total of 82 students in the 18 to 22 age category, as 78 + 4 = 82.
how many are 8 raised to 4 ???
Greyson completes a dive from a
cliff 75-feet above a river. It takes
him only 1.5 seconds to hit the
water and then another 0.5
second to descend 10 feet into the river
what’s the x axis and y axis?
Answer: y: height, x: time.
Step-by-step explanation:
The data we have is:
The initial position of Greyson is 75ft above the river.
He needs 1.5 seconds to hit the water, and other 0.5s tho reach the bottom of the river.
Then we have a relationship of height vs time.
The y axis will represent the heigth of Greyson, and the x-axis will represent the time, such that at the time x = 0 seconds, we have y = 75ft
The cost of milk is modeled by a linear equation where four quarts (one gallon) costs $3.09 while two quarts
(half-gallon) costs $1.65. Write the linear equation that expresses the price in terms of quarts. How much would
an eight-quart container of milk cost?
Answer:
linear equation to express the price is:
y=0.72x+0.21
An eight quarts will cost : $5.97
Step-by-step explanation:
linear equation represent y=mx+b
let x=quarts ( x=4, x=2)
y= price (3.09 and y=1.65 )
two points (4,3.09) and (2,1.65)
need to find the slope m:
y2-y1/x2-x1
(1.65-3.09)/(2-4) ⇒ m=0.72
y=0.72x+b find b at point (2,1.65)
1.65=0.72(2) +b ⇒ b=0.21
y=0.72x +0.21
check : point (4,3.09)
y=0.72(4) +0.21
y=3.09 ( correct)
An eight quarts will cost :
y=0.72(8)+0.21
y=5.97 dollars
The ratio of boys and girls in the class is 4:3. How many boys and girls are in the class if there are 35 students?
Answer:
20boys and 15girls
Step-by-step explanation:
Let no of boys be 4x
no of girls be 3x
4x+3x=35
7x=35
x=35/7
x=5
no of boys=4×5=20
no of girls=3×5=15
20+15=35 students
Use the rule "subtract 6" to create a sequence of 10 numbers starting with 100. (explanation/work needed)
Answer:
100 -6 = 94
94 - 6 = 88
88 - 6 = 82
82 - 6 = 76
76 - 6 = 70 We can then show and prove 70 -> 64.
64 -> 58
58 -> 52
52 -> 46
46 -> 40
As numbers that end in 0, decrease to units that end in 4,8,2,6,and back to zero.
= all numbers that end with 0 have numbers that end in 4,8,2,6,0 when subtracting 6.
As 6 x 10 = 60 and 60 +40 = 100
We cna prove 4+8+2+6 = 20
20+20 = 40 and would continue this pattern to get to 10 we can then see the sequence of how 30/6 and proves each 5 number coordinate being 4,8,2,6,0 until we get to 10.
We then find 4,-2,-8,-14,and-20 it skips out 2 and 6 here on the neutral line but then starts and changes the sequence end numbers to -26 -32, -38,-44 and -50. This proves that-2 and -8 has significance and shows us a real sum that on negative -2 -8 = 6
The inverse of the 40 marker in the positive shows us 60
and 60 -50 = 10 being our 2nd positive closest to zero.
These were repeated twice and show 40 deducted and a further 18 as 0 counts for 2 subtractions 100-6 70-6 just like 94 +6 = 100 and like 70+6 = 76 and 40+6 = 46
3 x 6 = 18
40+ 18 = 58
100-58 = 42 and shows us a reflection again with 4 and 2
not just 4+2 = 6 it shows is 4/2 = 2 42/2 = 21 and 7 being a divider represents the first sequence group of 10 from 100 being 70 and just as significant in a decrease of 6 in relation to 100.
100-70 = 30
30-6 = 24
24 / 6 = 4
and we mark 4 as our first unit with relation to 100 and its decrease of 6 in sequence.
This may help you remember that 30 x 100 = 3000 and would be increasing by 6 x 180 times. But when we decrease from here we find 2400 a likely number as 3000-600 - 2400
This may help you remember that 400/6 = 66.6666666667 and why decrease always ends up as negative when 400 x 6 = 2400 and is a much more dividable number. and that 400 is not dividable by 6 in the first place, and may be linked to why a neutral zero number may show 4 and 10 and -2 and -8 where all these numbers divide into 400 6 just doesn't work in any even hundred number below 1200 except for 600 as we know and recall 6 divides into 30 and 18 but not into 40, just counts back to inverse 40 from 100 as its counting 2 x 30 = 60. It does divide into 2400 and that is a midway point back down to 1800 from 3000. So this may help you remember divisors of larger numbers.
Express 3a2b-1 with positive exponents.
Answer:
a = 2b/3−1/3
Step-by-step explanation:
...........
Reduce 5/15 to its lowest terms
Answer:
The answer is 1/3
Answer:
1/3
Step-by-step explanation:
The factors of 5 are 1,5;
* The factors of 15 are 1,3,5,15.
We can see that the GCD is 5 because it is the largest number by which 5 y 15 can be divided without leaving any residue.
To reduce this fraction, simply divide the numerator and denominator by 5 (the GCF).
So, 5 /15
= 5÷5 /15÷5
= 1 /3
need help with this one
Answer:
At x intercept, x = 0
2.8(0)+5.7y+5.8=0
y=-5.8/5.7
=-1.02
At y intercept, y=0
2.8x+5.7(0)+5.8=0
x=-5.8/2.8
=-2.07
Answer:
X ans y intercepts are
xintercept (s) : (-2.0,0) you can roud if necessary
y intercept(s) : (0,-1.01754385) you can round if nessecary
Step-by-step explanation:
to find the [tex]x[/tex] and [tex]y[/tex] intercepts simply plug in [tex]o[/tex] to replace [tex]x[/tex] then when you solve for [tex]x[/tex] plug in [tex]x[/tex]to solve for [tex]y[/tex]
pls help with sum geometry
YES! quite easily.
I hope you can see the two pairs of corresponding angles between the parallel lines. they'll be equal
and then there's a pair of vertically opposite angle at centre.
that means all pairs of corresponding angles are equal, thus, triangles are similar by AAA
Answer:
[tex]\Large \boxed{\mathrm{D}}[/tex]
Step-by-step explanation:
The triangles can be proven by AA or Angle-Angle similarity.
[tex]\angle QUR \cong \angle TUS[/tex]
The vertical angles are congruent.
[tex]\angle R \cong \angle S[/tex]
The alternate interior angles are congruent.
8 more than a number
Answer:
[tex]\boxed{ 8 + x}[/tex]
Step-by-step explanation:
Hey there!
In most cases "the number" would be x.
So if the statement says 8 "more than a number",
It is saying 8 plus x or 8 + x.
Hope this helps :)
Answer:
x + 8 is the meaning.
Step-by-step explanation:
“more” means addition. Take the number as “x”, so it will be x + 8.
That's the answer.
All the edges of a cube have the same length. Tony claims that the formula SA = 6s, where s is the length of
each side of the cube, can be used to calculate the surface area of a cube.
a. Draw the net of a cube to determine if Tony's formula is correct.
b. Why does this formula work for cubes?
Frances believes this formula can be applied to calculate the surface area of any rectangular prism. Is
she correct? Why or why not?
d. Using the dimensions of Length, Width and Height, create a formula that could be used to calculate the
surface area of any rectangular prism, and prove your formula by calculating the surface area of a
rectangular prism with dimensions L = 5m, W = 6m and H=8m.
Answer:
Here's what I get
Step-by-step explanation:
a. Net of a cube
Fig. 1 is the net of a cube
b. Does the formula work?
Tony's formula works if you ignore dimensions.
There are six squares in the net of a cube.
If each side has a unit length s, the total area of the cube is 6s.
c. Will the formula work for any rectangular prism?
No, because a rectangular prism has sides of three different lengths — l, w, and h — as in Fig. 2.
d. Area of a rectangular prism
A rectangular prism has six faces.
A top (T) and a bottom (b) — A = 2×l×w
A left (L) and a right (R) — A = 2×l×h
A front (F) and a back (B) — A = 2×w×h
Total area = 2lw + 2lh + 2wh
If l = 5 m, w = 6 m and h = 8 m,
[tex]\begin{array}{rl}A &=& \text{2$\times$ 5 m $\times$ 6 m + 2$\times$ 5 m $\times$ 8 m + 2 $\times$ 6 m $\times$ 8 m}\\&=& \text{60 m}^{2} + \text{80 m}^{2} + \text{96 m}^{2}\\&=& \textbf{236 m}^{2}\\\end{array}[/tex]
PLEEEEEEEASE HELLLP What is the midpoint of segment RT with endpoints at (-5,2) and (1, -3)?
Answer:
-2, -1/2
Step-by-step explanation:
Step-by-step explanation:
The midpoint of a line segment between two points is given by
[tex]M = ( \frac{x1 + x2}{2} , \frac{y1 + y2}{2} )[/tex]
where ( x1 , y1) and ( x2 , y2) are the points
From the question
The midpoint of the line segment using points (-5,2) and (1, -3) is
[tex]M = ( \frac{ - 5 + 1}{2} , \frac{2 - 3}{2} )[/tex]
[tex]M = ( - \frac{ 4}{2} , - \frac{1}{2} )[/tex]
We have the final answer as
[tex]M = ( - 2, - \frac{1}{2} )[/tex]
Hope this helps you
Two buildings are 12m apart on the same horizontal level. From the top of the taller building, the angle of depression of the bottom of the shorter building is 48degrees and from the bottom, the angle of of elevation of the top of the shorter building is 36 degrees. Calculate the difference in the heights of the buildings
Answer:
4.61 m
Step-by-step explanation:
The angle of depression of the bottom of the shorter building from the top of the taller building = 48° equals the angle of elevation of the top of the taller building from the bottom of the shorter building
Using trig ratios
tan48° = H/d where H = height of taller building and d = their distance apart = 12 m
H = dtan48° = 12tan48° = 13.33 m
Also, the angle of elevation of the top of the shorter building from the bottom of the taller building is 36°
Using trig ratios
tan36° = h/d where h = height of shorter building
h =dtan36° = 12tan36° = 8.72 m
Now, the difference in height of the buildings is thus H - h = 13.33 m - 8.72 m = 4.61 m
Evaluate a + b for a= 34 and b= -6
Answer:
Hey there!
a+b
34+(-6)
34-6
28
Let me know if this helps :)
Let tan(x)=2/5 What is the value of tan(π−x) ?
Answer:
tan(π−2/5)
decimal form -0.42
Answer:
-0.42
Step-by-step explanation:
What is the measure of angle X?
====================================================
Explanation:
Focus on triangle BDH
Interior angles B and D are given to be 40 and 31 respectively. Interior angle H is unknown
For any triangle, the interior angles always add to 180
B+D+H = 180
40+31+H = 180
H+71 = 180
H = 180-71
H = 109
Interior angle H is 109 degrees for triangle BDH
The exterior angle is 180 minus this measure
exterior angle = 180 - (interior angle)
exterior angle = 180 - 109
exterior angle = 71
Note how this is the sum of interior angles B and D, so you could use the remote interior angle theorem here.
Suppose that $9500 is placed in an account that pays 9% interest compounded each year.
Assume that no withdrawals are made from the account.
Follow the instructions below. Do not do any rounding.
(a) Find the amount in the account at the end of 1 year.
so
(b) Find the amount in the account at the end of 2 years.
$
?
Answer:
$11286.95 second year
$10335 first year
Step-by-step explanation:
9% of 9500 is 855, 9500 plus 855 = 10335. (first year)
9% of 10335 is 931.95, and 10335+931.95 is 11286.95. (second year)
The amount in the account at the end of 1 year $10335 (first year)
The amount in the account at the end of 2 years $11286.95.
What is the compound interest?Compound interest is when you earn interest on both the money you've saved and the interest you earn.
Formula:
A = P(1 + {r}/{n})^{n.t}
here, we have,
$9500 is placed in an account that pays 9% interest compounded each year.
so, we get,
9% of 9500 is 855,
9500 plus 855 = 10335. (first year)
again,
9% of 10335 is 931.95,
and 10335+931.95 is 11286.95. (second year)
Hence, The amount in the account at the end of 1 year $10335 (first year)
The amount in the account at the end of 2 years $11286.95.
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Can someone please tell me how to solve this problem??!! I literally have to go back in math if I don’t pass this HELP!!
Answer:
D. 270° < φ < 360°Step-by-step explanation:
Imagine coordinate system
I quarter is where x>0 and y>0 {right top} and it is (0°,90°)
II quarter is where x<0 and y>0 {left top} and it is (90°,180°)
III quarter is where x<0 and y<0 {left bottom} and it is (180°,270°)
IV quarter is where x>0 and y<0 {right bottom} and it is (270°,360°)
Now, we have an angle wich vertex is point (0,0) and one of its sides is X-axis and the second lay at one of the quarters.
For the trig functons of an angle created by this second side always are true:
In first quarter all functions are >0
in second one only sine
in third one: tangent and cotangent
and in fourth one: cosine
{You can check this by selecting any point on the second side of angle and put it's coordinates to formulas of these functions:
[tex]\sin \phi=\dfrac y{\sqrt{x^2+y^2}}\,,\quad \cos \phi=\dfrac x{\sqrt{x^2+y^2}}\,,\quad \tan\phi=\dfrac yx\,,\quad \cot\phi=\dfrac xy[/tex] }
So:
sinφ<0 ⇒ III or IV quarter
tanφ<0 ⇒ I or IV quarter
IV quarter ⇒ φ ∈ (270°, 360°)
