Answers
Answer:
B. a×1
Step-by-step explanation:
This is because a×1 gives a result of a thus,a multiplying the identity element of multiplication
Related Questions
I need help I don't understand this at all.
Answers
please mark this answer as brainlist
100 POINTS AND BRAINLIEST FOR THIS WHOLE SEGMENT
a) Find zw, Write your answer in both polar form with ∈ [0, 2pi] and in complex form.
b) Find z^10. Write your answer in both polar form with ∈ [0, 2pi] and in complex form.
c) Find z/w. Write your answer in both polar form with ∈ [0, 2pi] and in complex form.
d) Find the three cube roots of z in complex form. Give answers correct to 4 decimal
places.
Answers
Answer:
See Below (Boxed Solutions).
Step-by-step explanation:
We are given the two complex numbers:
[tex]\displaystyle z = \sqrt{3} - i\text{ and } w = 6\left(\cos \frac{5\pi}{12} + i\sin \frac{5\pi}{12}\right)[/tex]
First, convert z to polar form. Recall that polar form of a complex number is:
[tex]z=r\left(\cos \theta + i\sin\theta\right)[/tex]
We will first find its modulus r, which is given by:
[tex]\displaystyle r = |z| = \sqrt{a^2+b^2}[/tex]
In this case, a = √3 and b = -1. Thus, the modulus is:
[tex]r = \sqrt{(\sqrt{3})^2 + (-1)^2} = 2[/tex]
Next, find the argument θ in [0, 2π). Recall that:
[tex]\displaystyle \tan \theta = \frac{b}{a}[/tex]
Therefore:
[tex]\displaystyle \theta = \arctan\frac{(-1)}{\sqrt{3}}[/tex]
Evaluate:
[tex]\displaystyle \theta = -\frac{\pi}{6}[/tex]
Since z must be in QIV, using reference angles, the argument will be:
[tex]\displaystyle \theta = \frac{11\pi}{6}[/tex]
Therefore, z in polar form is:
[tex]\displaystyle z=2\left(\cos \frac{11\pi}{6} + i \sin \frac{11\pi}{6}\right)[/tex]
Part A)
Recall that when multiplying two complex numbers z and w:
[tex]zw=r_1\cdot r_2 \left(\cos (\theta _1 + \theta _2) + i\sin(\theta_1 + \theta_2)\right)[/tex]
Therefore:
[tex]\displaystyle zw = (2)(6)\left(\cos\left(\frac{11\pi}{6} + \frac{5\pi}{12}\right) + i\sin\left(\frac{11\pi}{6} + \frac{5\pi}{12}\right)\right)[/tex]
Simplify. Hence, our polar form is:
[tex]\displaystyle\boxed{zw = 12\left(\cos\frac{9\pi}{4} + i\sin \frac{9\pi}{4}\right)}[/tex]
To find the complex form, evaluate:
[tex]\displaystyle zw = 12\cos \frac{9\pi}{4} + i\left(12\sin \frac{9\pi}{4}\right) =\boxed{ 6\sqrt{2} + 6i\sqrt{2}}[/tex]
Part B)
Recall that when raising a complex number to an exponent n:
[tex]\displaystyle z^n = r^n\left(\cos (n\cdot \theta) + i\sin (n\cdot \theta)\right)[/tex]
Therefore:
[tex]\displaystyle z^{10} = r^{10} \left(\cos (10\theta) + i\sin (10\theta)\right)[/tex]
Substitute:
[tex]\displaystyle z^{10} = (2)^{10} \left(\cos \left(10\left(\frac{11\pi}{6}\right)\right) + i\sin \left(10\left(\frac{11\pi}{6}\right)\right)\right)[/tex]
Simplify:
[tex]\displaystyle z^{10} = 1024\left(\cos\frac{55\pi}{3}+i\sin \frac{55\pi}{3}\right)[/tex]Simplify using coterminal angles. Thus, the polar form is:
[tex]\displaystyle \boxed{z^{10} = 1024\left(\cos \frac{\pi}{3} + i\sin \frac{\pi}{3}\right)}[/tex]
And the complex form is:
[tex]\displaystyle z^{10} = 1024\cos \frac{\pi}{3} + i\left(1024\sin \frac{\pi}{3}\right) = \boxed{512+512i\sqrt{3}}[/tex]
Part C)
Recall that:
[tex]\displaystyle \frac{z}{w} = \frac{r_1}{r_2} \left(\cos (\theta_1-\theta_2)+i\sin(\theta_1-\theta_2)\right)[/tex]
Therefore:
[tex]\displaystyle \frac{z}{w} = \frac{(2)}{(6)}\left(\cos \left(\frac{11\pi}{6} - \frac{5\pi}{12}\right) + i \sin \left(\frac{11\pi}{6} - \frac{5\pi}{12}\right)\right)[/tex]
Simplify. Hence, our polar form is:
[tex]\displaystyle\boxed{ \frac{z}{w} = \frac{1}{3} \left(\cos \frac{17\pi}{12} + i \sin \frac{17\pi}{12}\right)}[/tex]
And the complex form is:
[tex]\displaystyle \begin{aligned} \frac{z}{w} &= \frac{1}{3} \cos\frac{5\pi}{12} + i \left(\frac{1}{3} \sin \frac{5\pi}{12}\right)\right)\\ \\ &=\frac{1}{3}\left(\frac{\sqrt{2}-\sqrt{6}}{4}\right) + i\left(\frac{1}{3}\left(- \frac{\sqrt{6} + \sqrt{2}}{4}\right)\right) \\ \\ &= \boxed{\frac{\sqrt{2} - \sqrt{6}}{12} -\frac{\sqrt{6}+\sqrt{2}}{12}i}\end{aligned}[/tex]
Part D)
Let a be a cube root of z. Then by definition:
[tex]\displaystyle a^3 = z = 2\left(\cos \frac{11\pi}{6} + i\sin \frac{11\pi}{6}\right)[/tex]
From the property in Part B, we know that:
[tex]\displaystyle a^3 = r^3\left(\cos (3\theta) + i\sin(3\theta)\right)[/tex]
Therefore:
[tex]\displaystyle r^3\left(\cos (3\theta) + i\sin (3\theta)\right) = 2\left(\cos \frac{11\pi}{6} + i\sin \frac{11\pi}{6}\right)[/tex]
If two complex numbers are equal, their modulus and arguments must be equivalent. Thus:
[tex]\displaystyle r^3 = 2\text{ and } 3\theta = \frac{11\pi}{6}[/tex]
The first equation can be easily solved:
[tex]r=\sqrt[3]{2}[/tex]
For the second equation, 3θ must equal 11π/6 and any other rotation. In other words:
[tex]\displaystyle 3\theta = \frac{11\pi}{6} + 2\pi n\text{ where } n\in \mathbb{Z}[/tex]
Solve for the argument:
[tex]\displaystyle \theta = \frac{11\pi}{18} + \frac{2n\pi}{3} \text{ where } n \in \mathbb{Z}[/tex]
There are three distinct solutions within [0, 2π):
[tex]\displaystyle \theta = \frac{11\pi}{18} , \frac{23\pi}{18}\text{ and } \frac{35\pi}{18}[/tex]
Hence, the three roots are:
[tex]\displaystyle a_1 = \sqrt[3]{2} \left(\cos\frac{11\pi}{18}+ \sin \frac{11\pi}{18}\right) \\ \\ \\ a_2 = \sqrt[3]{2} \left(\cos \frac{23\pi}{18} + i\sin\frac{23\pi}{18}\right) \\ \\ \\ a_3 = \sqrt[3]{2} \left(\cos \frac{35\pi}{18} + i\sin \frac{35\pi}{18}\right)[/tex]
Or, approximately:
[tex]\displaystyle\boxed{ a _ 1\approx -0.4309 + 1.1839i,} \\ \\ \boxed{a_2 \approx -0.8099-0.9652i,} \\ \\ \boxed{a_3\approx 1.2408-0.2188i}[/tex]
What is the answer to the question 3x+5x
Answers
Answer:
8x
Step-by-step explanation:
=3x+5x
=8x
Select the correct answer.
Which statement best describes the solution to this system of equations?
3x + y= 17
x + 2y = 49
Ο Α.
It has no solution.
B.
It has infinite solutions.
O c.
It has a single solution: x = 15, y= 17.
OD.
It has a single solution: x = -3, y = 26.
Answers
Amy has four more 20c coins than 5c coins. The total value of all her 20c and 5c is $3.80. How many 5c coins does Amy have?
Answers
Answer: 12
Step-by-step explanation:
16 X 20c = 3.20
12 x 5c = 0.60
total is 3.80
Amy has 12 five c coins.
7)On subtracting 8 from x, the result is 2 . Form a linear
equation for the statement.
Answers
Answer:
8-x=2
-x=2-8
-x=-6
x=6
if 8 is subtract from 6answer is 2
Which series represents this situation? 1+1*7+1*7^ 2 +...1*7^ 6; 1+1*7+1*7^ 2 +...1*7^ 7; 7+1*7+1*7^ 2 +... 1*7^ 6; 7+1*7+1*7^ 2 +...1*7^ 7
Answers
Answer:
Step-by-step explanation:
The series is missing from the question. I will answer this question with a general explanation by using the following similar series:
[tex]\sum\limits^6_{n=0} 7^n[/tex]
Required
The series
To do this, we simply replace n with the values
[tex]\sum\limits^6_{n=0}[/tex] means n starts from 0 and ends at 6
[tex]\sum[/tex] means the series is a summation series
So, we have:
[tex]\sum\limits^6_{n=0} 7^n = 7^0 + 7^1 + 7^2 + ...... + 7^6[/tex]
[tex]\sum\limits^6_{n=0} 7^n = 1 + 7 + 7^2 + ...... + 7^6[/tex]
23. Insert the missing number.
4
6
9
14
23
40
?
138
266
Answers
Answer:
hey mate !!!
The pattern followed is
4x2-2= 8-2=6
6 x 2-3= 9
9 x 2- 4= 14
14 x 2-5 = 23
23 x 2-6= 40
40 x 2-7= 73
So, the next number will be 73.
Find the value of a. Round
the nearest tenth.
Answers
Answer:
side A should be about 44cm
En su cuenta bancaria, Sally tiene un saldo de -\$200.90−$200.90minus, dollar sign, 200, point, 90. Su amiga Shannon tiene un saldo bancario de -\$240.55−$240.55minus, dollar sign, 240, point, 55. ¿La cuenta bancaria de cuál amiga tiene más deuda
Answers
Answer:
Shannon
Step-by-step explanation:
Cuando se habla de lo que uno tiene, podemos usar números positivos.
Por ejemplo:
Pedro tiene 10 manzanas.
Para el caso de deudas, utilizamos números negativos, por ejemplo:
Pedro tiene -10 manzanas
Lo cual significa que Pedro debe 10 manzanas a alguien.
Entonces si le diéramos a Pedro 12 manzanas, el ahora tendría:
-10 + 12 = 2
Pedro tiene 2 manzanas, porque tuvo que entregar 10 de las 12 que le dimos para pagar su deuda.
Ahora vamos a resolver el problema:
La cuenta de Sally tiene un saldo de:
S = -$200.90
El signo negativo quiere decir que Sally tiene una deuda de $200.90
La cuenta de su amiga Shannon tiene un saldo de:
S' = -$240.55
De vuelta, el signo negativo quiere decir que Shannon tiene una deuda de $240.55
Con esto ya podemos concluir que la deuda de Shannon es mayor, por lo tanto Shannon es la que tiene más deuda.
Could I get the answer don’t understand
Answers
Answer:
DE = 21.4
Step-by-step explanation:
The parallel lines divide the transversals proportionally, that is
[tex]\frac{DE}{EB}[/tex] = [tex]\frac{DF}{FC}[/tex] , substitute values
[tex]\frac{DE}{10.7}[/tex] = [tex]\frac{32}{16}[/tex] = 2 ( multiply both sides by 10.7 )
DE = 21.4
Prachi was 555 kilometers east of her home when she began driving farther east at 707070 kilometers per hour. Let f(n)f(n)f, left parenthesis, n, right parenthesis be Prachi's distance from her home at the beginning of the n^\text{th}n th n, start superscript, start text, t, h, end text, end superscript hour of her drive.
Answers
Answer:
Following are the solution to the given question:
Step-by-step explanation:
Whenever she began to drive farther east, at 70 km per hour, Prachi was 5 km east of her home.
Let f(n) at the beginning of her nth hour drive be Prachi's distance to her home.
f is a sequence of arithmetic.
Write a series explicit form.
[tex]\to f(n) = 70n + 5[/tex]
Answer:
Arithmetic Sequence, f(n)=5+70(n-1)
Step-by-step explanation:
checked on khan
Anyone any good at math?
Is the relationship shown by the data linear? If so, model the data with an equation
Answers
Answer:
yes the x increases by 6 and the y decreases by 3.
y = -1/2x - 7/2
Step-by-step explanation:
find the slope :
(1,-4), (7, -7)
y2- y1 / x2 - x1
substitute those numbers and you get -1/2.
point slope form :
y - y1 = m(x- x1)
y - (-4) = -1/2 ( x - (1))
y+4 = -1/2(x-1)
slope intercept form :
y = -1/2x - 7/2
does this help ?
Which of the following numbers has exactly two significant digits? OA) 3.40 OB) 2.125 OC) 1.0475 OD) 0.00050
Answers
Answer:
Here, option (d) has significant digits. hence , option (d) ✓ is correct.7.
Which kind of function best models the data in the table? Graph the data and write an equation to model the data.
A. exponential; y = 3x – 1
B. linear; y = x – 1
C. quadratic; y = x2 – 1
D. linear; y = –x – 1
Answers
Answer:
D. linear; y = –x – 1
Step-by-step explanation:
Linear; y=-x - 1
The slope is negative since it’s decreasing. So it’s not the first equation. It’s not a quadratic equation because there is no forming U shape for this data. It’s not a exponential function because the slope is not 3 and a exponential function is in the form y=a(b)^x
...............................................................................................................................................
Answer:
The correct answer is D) linear; y = –x – 1
Step-by-step explanation:
To find this, use any values in the table and it will produce a true statement. This is how we check to see if a model is correct. See the two examples below for proof.
(4, 5)
y = -x - 1
-5 = -4 - 1
- 5 = -5 (TRUE)
(0, -1)
y = -x - 1
-1 = 0 - 1
-1 = -1 (TRUE)
In the figure, p is parallel to s. Trasnversals t and w intersect at point L.
Statement
What is the missing reason in step 3?
a.) Alternate interior angles along parallel lines are congruent
b.) Alternate exterior angles along parallel lines are congruent
c.) Corresponding angles along parallel lines are congruent
d.) Vertical angles are congruent
Answers
Option C
Corresponding angles along parrellel lines are conguerent
Answered by Gauthmath pls mark brainliest and comment thanks and click thanks
A seat’s position on a Ferris wheel can be modelled by the function y = 18 cos 2.8(x + 1.2) + 21, where y represents the height in feet and x represents the time in minutes. Determine the diameter of the Ferris wheel.
Answers
Step-by-step explanation:
A ball is thrown straight up from a rooftop 320 feet high. The formula below describes the ball's height above the ground, h, in feet, t seconds after it was thrown. The ball misses the rooftop on its way down and eventually strikes the ground. How long will it take for the ball to hit the ground? Use this information to provide tick marks with appropriate numbers along the horizontal axis in the figure shown.
h=-16t^2+16t+320
Can someone help please
Answers
Answer:
[tex]10^{-3}[/tex]
Step-by-step explanation:
Answer:
https://tex.z-dn.net/?f=10%5E%7B-3%7D
Step-by-step explanation:
What is the average rate of change of the function over the interval x = 0 to x = 8?
f(x)=2x−1/3x+5
Enter your answer, as a fraction, in the box.
Answers
====================================================
Work Shown:
Plug in x = 0
[tex]f(x) = \frac{2x-1}{3x+5}\\\\f(0) = \frac{2*0-1}{3*0+5}\\\\f(0) = \frac{0-1}{0+5}\\\\f(0) = -\frac{1}{5}\\\\[/tex]
Repeat for x = 8
[tex]f(x) = \frac{2x-1}{3x+5}\\\\f(8) = \frac{2*8-1}{3*8+5}\\\\f(8) = \frac{16-1}{24+5}\\\\f(8) = \frac{15}{29}\\\\[/tex]
Now use the average rate of change formula
[tex]m = \frac{f(b)-f(a)}{b-a}\\\\m = \frac{f(8)-f(0)}{8-0}\\\\m = \frac{15/29 - (-1/5)}{8}\\\\m = \frac{15/29 + 1/5}{8}\\\\m = \frac{(15/29)*(5/5) + (1/5)*(29/29)}{8}\\\\m = \frac{75/145 + 29/145}{8}\\\\[/tex]
[tex]m=\frac{104/145}{8}\\\\m = \frac{104}{145} \div \frac{8}{1}\\\\m = \frac{104}{145} \times \frac{1}{8}\\\\m = \frac{104*1}{145*8}\\\\m = \frac{104}{1160}\\\\m = \frac{13}{145}\\\\[/tex]
Find the surface area of the cylinder in terms of T. 9 cm 19 cm Not drawn to scale O 211.5 cm 2 0 382.57 cm 2. O 333 77 cm2 o 504 лcm
Answers
Answer:
hey the answer is cylinder= 211.5л!
The function f(x) = x2 has been translated 9 units up and 4 units to the right to form the function g(x). Which represents g(x)?
g(x) = (x + 9)2 + 4
g(x) = (x + 9)2 − 4
g(x) = (x − 4)2 + 9
g(x) = (x + 4)2 + 9
Answers
Answer:
The function that represents g(x) is the third choice: g(x) = (x − 4)^2 + 9
Step-by-step explanation:
The original function has been shifted 9 units up (a vertical transformation). To show a vertical transformation, all we have to do is either add or subtract at the end of the function.
To show a shift upwards, we add the value of change.
To show a shift downwards, we subtract the value of change.
In this case, the original function f(x) = [tex]x^{2}[/tex] was translated 9 units up. Since we shifted up, we simply add 9 to the end of the function: g(x) = [tex]x^{2}[/tex] + 9
The original function has also been shifted 4 units to the right. This is a horizontal transformation. To show a horizontal transformation, we need to either add or subtract within the function (within the parenthesis).
To show a shift to the left, we add the value of change.
To show a shift to the right, we subtract the value of change.
*Notice: Moving left does NOT mean to subtract while moving right does NOT mean to add. The rules above are counterintuitive so pay attention when doing horizontal transformations.
In this case, the original function f(x) = [tex]x^{2}[/tex] was translated 4 units to the right. Since we shifted right, we must subtract 4 units within the function/parenthesis: g(x) = [tex](x-4)^{2}[/tex]
When we combine both vertical and horizontal changes, the only equation that follows these rules is the third choice: g(x) = (x − 4)^2 + 9
Answer: C
Step-by-step explanation:
solve this question :
-10k2+7
Answers
Answer:
-10k×2+7
= -20k+7
Step-by-step explanation:
is the answer
How do you find the diameter of a quarter circle?
Answers
Answer:
um 1/4
Step-by-step explanation:
this is the question. please help me
Answers
Answer:
a.) 19.2cm
b.) 0.15375cm
Step-by-step explanation:
Cylinders are similar, so:
h1 / r1 = h2 / r2
8cm / 5cm = h2 / 12cm
h2 = (8cm × 12cm) / 5cm
h2 = 19.2cm
Same for b
32000cm2 / 246cm = 20cm2 / length
length = ((20 × 246) / 32000) cm
length = 0.15375cm
Intuitively, does it make sense that all circles are similar? Why or why not?
Answers
Answer with explanation:
Yes, each point on a circle is a fixed distance from the center of the circle. This is called the radius of the circle. By definition, all radii of a circle are equal.
Similar polygons have corresponding sides in similar proportion. Regardless of how large a circle is, each point on the circle will still be a fixed distance away from center of the circle. Therefore, the radii are in a constant proportional and all circles are similar.
Rebecca can paint a room in 12 hours Guadalupe can paint the same room in 16 hours how long does it take for both Rebecca and Guadalupe to paint the room if they are working together
Answers
Guadalupe can paint in 16hrs (and Guadalupe G)
How long ? = (RxG) x 24 divided by 2
(12x16)24/2
2304/60
38.4hrs.
what is the radius of the semicircle
Answers
20
Step-by-step explanation:
Hint: Use the Pythagorean Theorem
———————————————————
We’ll just listen to what the hint says
Pythagorean theorem: a^2 + b^2 = c^2
where a = 16 b = 12 and c = radius
16^2 + 12^2 = c^2
256 + 144 = c^2
c^2 = 400
square root 400
sqrt rt 400 = 20
The radius of the semicircle is 20
n the graph below determine how many real solutions the quadratic function has, and state them, if applicable. List solutions in order from left to right on the graph, or least to greatest. If the function has only one solution, type the solution in both of the boxes. If there are no real solutions type “none” in both boxes.
Answers
Answer:
There are no real solutions.
Step-by-step explanation:
There are 3 options.
2 real solutions: This happens if in the graph, each arm intersects the x-axis, this means that there are two different values of x such that the equation:
a*x^2 + b*x + c
is equal to zero.
Another way to see this, is if the determinant:
b^2 - 4*a*c
is larger than zero.
1 real solution: This happens when the vertex of the graph intersects the x-axis. This means that there is a single value of x such that:
a*x^2 + b*x + c
is equal to zero.
Another way to see this is if the determinant:
b^2 - 4*a*c
is larger equal zero.
No real solution: if in the graph we can not see any intersection of the x-axis, then we do not have real solutions (only complex ones).
Another way to see this is if the determinant:
b^2 - 4*a*c
is smaller than zero.
Now that we know this, let's look at the graph.
We can see that the vertex is below the x-axis, and the arms of the graph go downwards. So the arms will never intersect the x-axis (and neither the vertex).
So the graph does not intersect the x-axis at any point, which means that there are no real solutions for the quadratic equation.
The correct answer would be "none"
đồ thị hàm số có bao nhiêu tiệm cận
Answers
Answer:
c
Step-by-step explanation:
Multiply: (2x+y) (n2-3xy+y2)
Answers
Answer:
[tex]{ \tt{(2x + y)( {n}^{2} - 3xy + {y}^{2} )}} \\ = { \tt{(2x {n}^{2} - 3 {x}^{2}y + 2x {y}^{2} + {n}^{2}y - 3x {y}^{2} + {y}^{3} )}} \\ = { \tt{ {y}^{3} - xy(y + 3x) + {n}^{2} y }}[/tex]
Hello!
(2x+y) (n2-3xy+y2)
2x* n²= 2xn²
2x* -3xy = -6x²y
2x* y² = 2xy²
y*n² = yn²
y*-3xy = -3xy²
y* y² = y³
=>
2xn²- 6x²y + 2xy² +yn²- 3xy² +y³
