Answer:
A)
Step-by-step explanation:
HELP PLS!! ILL GIVE POINTS !! :(( m
Find the product of the complex numbers. Express your answer in
trigonometric form.
Z1 =5(cos15° + i sin 15°)
Z2=3(cos70° + i sin 70°)
A. 8(cos85° + isin85°)
B. 2 (cos(-55°) + i sin(-55°))
C. 2 (cos305° + i sin 305°)
D. 15(cos85° + i sin85°)
Answer: Choice D
15(cos85° + i sin85°)
===========================================================
Explanation:
Let's say we had these two general complex numbers, which are in polar form.
[tex]z_1 = r_1*\left(\cos(\theta_1)+i*\sin(\theta_1)\right)\\\\z_2 = r_2*\left(\cos(\theta_2)+i*\sin(\theta_2)\right)\\\\[/tex]
We can abbreviate them into the shorthand form
[tex]z_1 = r_1*\text{cis}(\theta_1)\\\\z_2 = r_2*\text{cis}(\theta_2)\\\\[/tex]
The notation "cis" stands for "cosine i sine".
Now that we have those complex numbers set up, multiplying them is as simple as saying this:
[tex]z_1*z_2 = (r_1*r_2)*\text{cis}(\theta_1+\theta_2)[/tex]
We do two basic things:
Multiply the r values out frontAdd the theta values inside the the cis function---------------------------------------
With all that in mind, let's tackle the problem your teacher gave you.
The given complex numbers
[tex]z_1 = 5*\left(\cos(15^{\circ})+i*\sin(15^{\circ})\right)\\\\z_2 = 3*\left(\cos(70^{\circ})+i*\sin(70^{\circ})\right)\\\\[/tex]
abbreviate into
[tex]z_1 = 5*\text{cis}(15^{\circ})\\\\z_2 = 3*\text{cis}(70^{\circ})\\\\[/tex]
then those multiply to
[tex]z_1*z_2 = (r_1*r_2)*\text{cis}(\theta_1+\theta_2)\\\\z_1*z_2 = (5*3)*\text{cis}(15+70)\\\\z_1*z_2 = 15\text{cis}(85^{\circ})\\\\z_1*z_2 = 15\left(\cos(85^{\circ})+i\sin(85^{\circ})\right)\\\\[/tex]
which is why choice D is the final answer.
17. Find an equation of the straight line that is perpendicular to x - y = 5 and passes through the point (8, -1).
18. Find the equation of the line in slope-intercept form that passes through the points (12, 4) and (4, 6)
Answer:
17.y=-x+12
18.y=-1/4x+7
Step-by-step explanation:
17.a Solve for y (y=-5+x)
17. b Reciprocal (y=-1x-5)
17. c Subsitute equation into (8,-1) (-1=-13=y=x+12)
18.a Subtract y values and x values= (6-4)/(4-12)=2/-8=-1/4, this will be your slope
18. b Plug in -1/4 into either of the two ordered pairs to find y value=(12,4)=(4=-3)=y value=7.
18. c=y=-1/4x+7
Find the third angle of a triangle if two of its angles are equal to:
25 degrees and 80 degrees
and
25 degrees and 120 degrees
Answer:
60 degrees
Step-by-step explanation:
Answer:
75 degrees, 35 degrees
Step-by-step explanation:
a. Adding 25 degrees and 80 degrees yields 105 degrees. The third angle of the given triangle must therefore be 180 degrees less 105 degrees, or 75 degrees.
b. Adding 25 degrees and 120 degrees yields 145 degrees. The third angle of the given triangle must therefore be 180 degrees less 145 degrees, or 35 degrees.
Find the slope of the line that passes through the following points: (0, -3), (-6,8)
Answer:
-11/6
Step-by-step explanation:
To find the slope, we use the formula
m = ( y2-y1)/(x2-x1)
= ( 8- -3)/( -6 - 0)
= (8+3)/(-6-0)
= 11 / -6
= -11/6
Helpppppppp???????????????
Answer:
A, [tex]{x | x<-2}[/tex]
Step-by-step explanation:
We have the inequality as
[tex]3x<-6[/tex]
We can simplify this inequality a little bit more by dividing 3 from both sides.
That gets us
[tex]x<-2[/tex]
We can see the only answer that has this is A.
\HURRY PLZ
evaluate k divided (-11) for k=33
Answer:
-3
Step-by-step explanation:
k/-11
Let k =33
33/ -11
-3
Answer:
-3
Step-by-step explanation:
33/-11 = -3
NOTE
division and multiplication = negative
addition and subtraction are a pair.
I hope this helped!
the angle of elevation to a nearby tree from a point of the ground is measured to be 39 degrees
Answer:
66.4
Step-by-step explanation:
tan(39)=x/82
x=tan(39)×82
x=66.4 (rounded to the nearest tenth)
Answered by GAUTHMATH
x.(9x-1).(x+2)-x(3x-1).(3x+1)
Answer:
Sorry if i'm wrong.
=6x² + 16x - 2
let the cp be rs x. if a man gains 20% profit by selling an article for rs 816. find cp
Answer:
Let, the c.p be x.
Given,
profit % = 20%
S.P = rs 816
c.p = x
We know,
profit = p% of c.p
= [tex]\frac{20}{100}[/tex] * x
= [tex]\frac{x}{5}[/tex]
now,
C.p = profit + s.p.
x = [tex]\frac{x}{5}[/tex] + 816
x = [tex]\frac{x+ 4080}{5}[/tex]
5x = x + 4080
5x-x = 4080
4x = 4080
x = [tex]\frac{4080}{4}[/tex]
x = Rs 1080
Hence, the c.p is Rs. 1080
Which expression is equivalent to d - 8 - 8d?
Answer:
−7d−8
Step-by-step explanation:
Subtract 8d from d.
(4,-5) with slope of 2
that's a point slope form so
y +5 = 2(x -4)
-3c-4=2
---------------
Answer:
Solution given:
-3c-4=2
add 4 on both side
-3c-4+4=2+4
-3c=6
divide both side by -3
-3c/-3=6/-3
c=-2
Answer:
[tex]-3c = 2 + 4 \\ -3c = 6 \\ c = \frac{6}{-3} \\ c = -2 [/tex]
An athlete throws her javelin 9.5 yards. She throws it this distance 2 times. How far she throw her javelin in total
Answer: 19 yards
Step-by-step explanation: 9.5x2=19
please help, i will give brainliest!
Answer:
yes please, ask the question
Find the measure of the numbered angles.
Angle 1 =
Angle 2 =
Angle 3 =
Angle 4 =
Angle 5 =
Angle 6 =
Angle 7 =
Angle 8 =
Explanation in pictures.
Hope this helps!! Have a good day!
which kind of triangle is shown?
A. Acute isosceles
B. Right scalene
C. Right isosceles
D. Acute scalene
Answer: B
Step-by-step explanation:
Acute isosceles: angle less than 90, 2 equal sides
Right scalene: right angle, different side lengths
RIght isosceles: right angle, 2 equal sides
Acute scalene: angle less than 90, different side lengths
Joylin is writing an equation to model the proportional relationship between y, the total cost in dollars of downloading videos from a website, and x, the number of videos downloaded. She knows that the total cost to download 3 videos was $12. Her work to find the equation is shown below.
Joylin’s Work
Step 1
k = StartFraction 3 over 12 EndFraction = 0.25
Step 2
y = 0.25 x
Where did Joylin make her first error?
Answer:
Step-by-step explanation:
Jocelyn was attempting to find out how much she will be charged per download. She has the fraction upside down. To find the amount of money per download, the fraction should be $12/3downloads to get $4/1download. That is the slope of the equation, the rate of change or, for us, the fact that your cost will go up $4 for every single video you download. The equation would then be
y = 4x
The way she has it, we are paying only a quarter for a download. If that be the case, for 3 downloads we would only be paying .75, but it says we pay $12, so we know something is wrong right there.
Answer:
The answer is A
Step-by-step explanation:
Choose the algebraic description that maps the image ΔABC onto ΔA′B′C′.
Question 2 options:
(x,y) → (x – 4,y)
(x,y) → (x,y + 4)
(x,y) → (x,y – 4)
(x,y) → (x + 4,y)
Answer:
(x,y+4)
Step-by-step explanation:
This shows a translation of 4 units up, so the y coordinate increases by 4. Please mark brainliest as I need 1 more to move up. It would be much appreciated.
Answer:B
Step-by-step explanation:
Enter an inequality that represents the graph in the box.
Answer:
stop cheating
Step-by-step explanation:
get smart
Find the area of the sector in
terms of pi.
90°
24
Area = [?]
TT
Answer:
288*pi
Step-by-step explanation:
Area=2*pi*(24)^2*(90/360)=288*pi
Need help ASAP!!!Please explain how to solve the problem
Answer:
Step-by-step explanation:
Translate to an equation, then solve.
Nineteen less than six times a number is equal to 11 more than four times the number?
What is the number?
Answer:
15Step-by-step explanation:
Let the number is x, then we have:
6x - 19 = 4x + 116x - 4x = 11 + 192x = 30x = 15Geometry, please answer question ASAP
Answer:
XY = 24
Step-by-step explanation:
In similar triangles, the corresponding sides are in same ratio.
[tex]\frac{AC}{XZ}=\frac{AB}{XY}\\\\\frac{x+6}{30}=\frac{16}{2x-4}[/tex]
Cross multiply,
(x + 6 )(2x-4) = 16*30
Use FOIL method
x*2x + x*(-4) + 6*2x + 6*(-4) = 480
2x² - 4x + 12x - 24 = 480 {Combine like terms}
2x² + 8x - 24 = 480
2x² + 8x - 24 - 480 = 0
2x² + 8x - 504 = 0
Divide the entire equation by 2
x² + 4x - 252 = 0
Sum = 4
Product = -252
Factors = 18 , -14 {18 +(-14) = 4 & 18*(-14) = -254 }
x² + 4x - 252 = 0
x² + 18x - 14x - 252 = 0 {Rewrite middle term}
x(x + 18) - 14(x + 18) = 0
(x + 18)(x - 14) = 0
x - 14 = 0 {Ignore x + 18 = 0 as measurement will not come in negative}
x = 14
XY = 2x - 4
= 2*14 -4
= 28 - 4
= 24
form a polynomial whose factors are (x+1) , (x+2) and (x-3)
Answer:
x³-7x-6
Step-by-step explanation:
Find the products of the factors
(x+1)(x+2)(x-3)
x²+3x+2(x-3)
x³+3x²+2x-3x²-9x-6
x³-7x-6
I need help with this does anybody know the answer
Answer:
X = 50; Y = 50
Answers are the same by following the correct order of operations.
Step-by-step explanation:
This problem deals with the correct order of operations. Multiplication is done before addition.
22 * 2 + 6 = X
44 + 6 = X
X = 50
6 + 22 * 2 = Y
6 + 44 = Y
Y = 50
The answers are the same despite the order in which the operations were written since by following the correct order of operations, you must do the multiplication first in each chase.
Help please anyoneee
Answer:
here's the answer to your question
3
Select the correct answer.
The angle of depression between the top of a 100-foot cliff and a ship approaching the shore is 37°.
cliff top
37°
100
feet
37°
ship
d
What is the approximate distance, d, between the bottom of the cliff and the ship?
ОА
166.2 feet
OB. 60.2 feet
ОС.
75.4 feet
OD.
132.7 feet
Reset
Next
Answer:
132.7 feet.
Step-by-step explanation:
tan 37 = height of cliff / distance of the ship
= 100/d
d = 100/tan37
= 132.7 feet.
(b) Work out the probability Jennifer hits the Bullseye at least once.
Can someone work this out for me ?
Answer:
1/2
Step-by-step explanation:
Filling out the tree diagram,
On the first throw, there is a 4/4 = 100%* chance Jennifer hits or misses. Therefore, the chance she misses is equal to the difference between
(chance she hits or misses) - (chance she hits) = 4/4 - 1/4 = 3/4
For the second throw, the chance she hits is independent of whether she hits or misses on the first throw. This means that it does not matter whether she hits or misses on the first throw; her chance to hit the second throw will always be 1/3. Therefore, 1/3 can go into the hit category on each hit line on the second throw, and in the miss category, we can put
100% - 1/3 = 1 - 1/3 = 3/3 - 1/3 = 2/3
For Jennifer to hit the bullseye at least once, she must either:
- Hit and then hit
- Hit and then miss
- Miss and then hit
From this, we can determine that if Jennifer hits the first bullseye, she will have hit it at least once, no matter what. Therefore, Jennifer must either:
- Hit the first one
- Miss and then hit
In probability, OR /either means that we add the probabilties. The probability that she hits the first one is 1/4, and the probability that she misses and then hits is
(probability she misses the 1st one) * (probability she hits the second one). We know to multiply here because both scenarios must happen, and for AND probabilities, we multiply. We thus have
(3/4) * (1/3) = 3/12 = 1/4 as the probabilty that she misses then hits, and 1/4 as the probability that she hits the first one. We add these up to get 1/4 + 1/4 = 2/4 = 1/2 as our probability that she hits the bullseye at least once
* we know 4/4 = 100% because 100% = 1, and anything divided by itself is equal to 1.
How many more unit tiles must be added to the function f(x)=x2−6x+1 in order to complete the square? 1 6 8 9
Answer:
easy
Step-by-step explanation:
8
Answer:
its 8
Step-by-step explanation:
Solve the system by substitution.
y = -3x + 17
2x + 3y = -5
Answer:
(8, -7)
Step-by-step explanation:
Hi there!
We are given this system:
y=-3x+17
2x+3y=5
And we want to solve the system
Let's solve it by substitution.
In the first equation, we are given y=-3x+17, which we can substitute -3x+17 as y into the second equation
2x+3(-3x+17)=5
Now do the distributive property
2x+-9x+51=-5
Combine like terms
-7x+51=-5
Subtract 51 from both sides
-7x=-56
Divide both sides by -7
x=8
Now substitute 8 as the value of x in y=-3x+17 to find the value of y
y=-3(8)+17
y=-24+17
y=-7
The answer is x=8, y=-7. If you need it as a point, it's (8, -7)
Hope this helps!