1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Oxana [17]
3 years ago
5

Use your knowledge of trig identities to find the trig value below.

Mathematics
1 answer:
sveticcg [70]3 years ago
5 0
I just switched Theta for x so i can type it:

secx = 1/cosx

secx = 1/(1/3)

secx = 3
You might be interested in
Question 1 answer this
Mademuasel [1]
Answer A and Answer D along with the ones you picked beforehand
8 0
2 years ago
Read 2 more answers
Find all the complex roots. Write the answer in exponential form.
dezoksy [38]

We have to calculate the fourth roots of this complex number:

z=9+9\sqrt[]{3}i

We start by writing this number in exponential form:

\begin{gathered} r=\sqrt[]{9^2+(9\sqrt[]{3})^2} \\ r=\sqrt[]{81+81\cdot3} \\ r=\sqrt[]{81+243} \\ r=\sqrt[]{324} \\ r=18 \end{gathered}\theta=\arctan (\frac{9\sqrt[]{3}}{9})=\arctan (\sqrt[]{3})=\frac{\pi}{3}

Then, the exponential form is:

z=18e^{\frac{\pi}{3}i}

The formula for the roots of a complex number can be written (in polar form) as:

z^{\frac{1}{n}}=r^{\frac{1}{n}}\cdot\lbrack\cos (\frac{\theta+2\pi k}{n})+i\cdot\sin (\frac{\theta+2\pi k}{n})\rbrack\text{ for }k=0,1,\ldots,n-1

Then, for a fourth root, we will have n = 4 and k = 0, 1, 2 and 3.

To simplify the calculations, we start by calculating the fourth root of r:

r^{\frac{1}{4}}=18^{\frac{1}{4}}=\sqrt[4]{18}

<em>NOTE: It can not be simplified anymore, so we will leave it like this.</em>

Then, we calculate the arguments of the trigonometric functions:

\frac{\theta+2\pi k}{n}=\frac{\frac{\pi}{2}+2\pi k}{4}=\frac{\pi}{8}+\frac{\pi}{2}k=\pi(\frac{1}{8}+\frac{k}{2})

We can now calculate for each value of k:

\begin{gathered} k=0\colon \\ z_0=\sqrt[4]{18}\cdot(\cos (\pi(\frac{1}{8}+\frac{0}{2}))+i\cdot\sin (\pi(\frac{1}{8}+\frac{0}{2}))) \\ z_0=\sqrt[4]{18}\cdot(\cos (\frac{\pi}{8})+i\cdot\sin (\frac{\pi}{8}) \\ z_0=\sqrt[4]{18}\cdot e^{i\frac{\pi}{8}} \end{gathered}\begin{gathered} k=1\colon \\ z_1=\sqrt[4]{18}\cdot(\cos (\pi(\frac{1}{8}+\frac{1}{2}))+i\cdot\sin (\pi(\frac{1}{8}+\frac{1}{2}))) \\ z_1=\sqrt[4]{18}\cdot(\cos (\frac{5\pi}{8})+i\cdot\sin (\frac{5\pi}{8})) \\ z_1=\sqrt[4]{18}e^{i\frac{5\pi}{8}} \end{gathered}\begin{gathered} k=2\colon \\ z_2=\sqrt[4]{18}\cdot(\cos (\pi(\frac{1}{8}+\frac{2}{2}))+i\cdot\sin (\pi(\frac{1}{8}+\frac{2}{2}))) \\ z_2=\sqrt[4]{18}\cdot(\cos (\frac{9\pi}{8})+i\cdot\sin (\frac{9\pi}{8})) \\ z_2=\sqrt[4]{18}e^{i\frac{9\pi}{8}} \end{gathered}\begin{gathered} k=3\colon \\ z_3=\sqrt[4]{18}\cdot(\cos (\pi(\frac{1}{8}+\frac{3}{2}))+i\cdot\sin (\pi(\frac{1}{8}+\frac{3}{2}))) \\ z_3=\sqrt[4]{18}\cdot(\cos (\frac{13\pi}{8})+i\cdot\sin (\frac{13\pi}{8})) \\ z_3=\sqrt[4]{18}e^{i\frac{13\pi}{8}} \end{gathered}

Answer:

The four roots in exponential form are

z0 = 18^(1/4)*e^(i*π/8)

z1 = 18^(1/4)*e^(i*5π/8)

z2 = 18^(1/4)*e^(i*9π/8)

z3 = 18^(1/4)*e^(i*13π/8)

5 0
1 year ago
The cost of Samantha's 15th birthday party depends on the number guest. The hall charges $250 for the use of the hall plus $12 p
Scorpion4ik [409]

Answer:

Equation: y=x(12)+250

Total cost: $550

3 0
2 years ago
Which of the following circles have their centers in the second quadrant? Check all that apply.
ivann1987 [24]
The given circles are given in standard form:
(x - xc)² + (y - yc)² = r²

The second quadrant is the one that has negative x coordinates and positive y coordinates.

This said, let's see all your options:
A) (x - 5)² + (y - 6)² = 25
xc = -(-5) = +5
yc = -(-6) = +6
C (5 , 6) is in the first quadrant.

B) (x + 1)² + (y - 7)² = 16
xc = -(+1) = -1
yc = -(-7) = +7
C (-1 , 7) is in the second quadrant.

C) (x - 4)² + (y + 3)² = 32
xc = -(-4) = +4
yc = -(+3) = -3
C (4, -3) is in the fourth quadrant.

<span> D) (x + 2)² + (y - 5)²= 9</span>
xc = -(+2) = -2
yc = -(-5) = +5
C (-2 , +5) is in the second quadrant.

Therefore, the correct answers are B and D.
7 0
3 years ago
Solve the equation -7 = y for x.
Harlamova29_29 [7]

Answer:

x = 4y+28

Step-by-step explanation:

x/4 -7 = y

Solve for x

Add 7 to each side

x/4  -7+7 = y+7

x/4 = (y+7)

Multiply each side by 4

x/4*4 = 4(y+7)

x = 4y+28

5 0
3 years ago
Read 2 more answers
Other questions:
  • They is 1440 cubic inches and the area of the base is 144 what is the hight
    14·1 answer
  • Find the value of y and x in the figure
    6·1 answer
  • The arithmetic mean of ten boys is 8 years, 6 months one of them is 13 years old. Then the arithmetic mean of remaining 9 boys i
    6·1 answer
  • A 2,400 deposit for 8 years compounded at an annual interest rate of 4.5%
    6·2 answers
  • What is 3 8/9 - 1 5/8
    5·2 answers
  • Solve for x.<br> (x - 3)2 = 64
    9·2 answers
  • What is the #1 rule of inequalities that<br> makes them different than equations?
    15·1 answer
  • Help me solve this problem please
    13·1 answer
  • I will give brainliest to the right answer&lt;3
    14·1 answer
  • How do you solve the inequality of -11.3 is equal to or greater than -4.7 + 4x​
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!