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
Lunna [17]
3 years ago
12

If cos x=−6/7, and 90°

Mathematics
1 answer:
ankoles [38]3 years ago
4 0

Answer: 0.4693877

Step-by-step explanation:

Given that:

cos x=−6/7,

From trigonometry :

Cosx + sinx = 1

Cos2x = cos(x + x)

Recall the double angle identity:

Cos2x = 2cos^2x - 1

Sin2x = 1 - 2sin^2x

Since cosx = - 6/7

Then

Cos2x = 2cos^2x - 1

Cos2x = 2cosx^2 - 1

Cos2x = 2(-6/7)^2 - 1

Cos2x = 2(36/49) - 1

Cos2x = 2 * (72/98) - 1

Cos2x = (2 * 0.7346938) - 1

Cos 2x = ( 1.4693877 - 1)

Cos2x = 0.4693877

You might be interested in
How many 1/4 cup servings are in 4 cups of oatmeal ?
Wewaii [24]
4 1/4 cup servings
hope this helps
5 0
3 years ago
Read 2 more answers
I will mark brainliest
Novosadov [1.4K]

Answer: 48.54101966249685

Step-by-step explanation:

8 0
3 years ago
Read 2 more answers
What’s the piremeter of a polygon
Burka [1]

Answer:

the length of all sides added together

6 0
3 years ago
Evaluate ( 4 upon 3 ) -2<br><br><br>please amswer fast​
Taya2010 [7]
<h2><u>Solution</u></h2>

\frac{4}{3}  - 2 \\  \\   = \frac{4 - 6}{ 3}  \\  \\  =  \frac{ - 2}{3}

<h3>Hope This Helps You ❤️</h3>
6 0
3 years ago
100 is divisible by which of the following numbers 2,3,4,5,6,9 or 10?
pochemuha
The correct answer is B: 2,4,5, 10

We know that 100 is not divisible by 3 because 100/3 is 33.33 repeating, which is an irrational number.

We also know that 100 is not divisible by 6 because 100/6 is 16.66 repeating which is also an irrational number.

100/2=50 (rational)
100/4=25 (rational)
100/5=20 (rational)
100/10=20 (rational)

Hope this helps!
6 0
3 years ago
Other questions:
  • 438<br>x 56<br><br><br>equels what?​
    11·2 answers
  • The radius of a cylindrical gift box is ​(4x + 1​) inches. The height of the gift box is three times the radius. What is the sur
    13·2 answers
  • Find the product of monomials<br> 3a^4b^-2 and 2a^7b^-1
    11·1 answer
  • The South Coast Air Basin (Los Angeles, Orange, and San Bernardino counties) does not meet the air quality standards for carbon
    8·1 answer
  • Larry measures the lens on a magnifying glass and calculates that it has an area of 50.24 square centimeters. What is the lens's
    14·2 answers
  • A right triangle kin the coordinate plane has vertices at (0,0), (0,8)c, and (6,0). The triangle is rotated 90° counter clockwis
    12·1 answer
  • <img src="https://tex.z-dn.net/?f=%5Cfrac%7B%28csc%20x%2B1%29%28csc%20x-1%29%7D%7Bcsc%5E2x%7D%5C%5C" id="TexFormula1" title="\fr
    5·1 answer
  • Use the matrix tool to solve the system of equations. Choose the correct
    15·1 answer
  • What is the solution to the system below? <br> x + 3y = 0<br> 2x - y = -7
    6·1 answer
  • Triangle JKL is transformed to create triangle J'K'L'. The angles in both triangles are shown.
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!