All categories

3 years ago

Find the value of cos(20) using double-angle formula given: 20 points !!! I need help ASAP

Mathematics

1 answer:

MissTica3 years ago

3 0

the correct answer is -1/9

explanation

cos(2A)

=cos(A+A)

=cosA.cosA - sinA.sinA

=cos ^2A- sin^2A

=cos^2A - 1 + cos^2A

=2cos^2A-1

putting the value of cos A -2/3

2*(-2/3)^2-1

=2*4/9-1

=8/9-1

=-1/9

here is put theta as A because I don't find theta symbol

don't forget to mark as brainllest answer

You might be interested in

What is the slope and y-intercept of the line 2x + 3y = 12

sdas [7]

Answer:

2/3 is the slope and 4 is the 4 intersept

Step-by-step explanation:

7 0

3 years ago

What is the value of 2x – 17 when x=-3?

Maksim231197 [3]

Answer:

-23

Explanation:

To find the value of the expression when x = -3, we simply put in -3 wherever we find x - doing this gives

$2(-3)-17$ $=-6-17$ $=-23$

which is our answer!

4 0

1 year ago

Which graph represents y=⌈x⌉over the domain 2≤x≤5 ?

ludmilkaskok [199]

Answer:

good job❤

Step-by-step explanation:

4 0

3 years ago

Read 2 more answers

Factor 4x^4yz-16y^3z

Iteru [2.4K]

Answer:

Step-by-step explanation:

$4x^4yz-16y^3z\\\\4x^4yz=4yz\cdot x^4\\\\16y^3z=4yz\cdot4y^2\\\\4x^4yz-16y^3z=4yz\cdot x^4-4yz\cdot4y^2=4yz(x^4-4y^2)\\\\x^4-4y^2=x^{2\cdot2}-2^2y^2=(x^2)^2-(2y)^2=(x^2-2y)(x^2+2y)\\\\Used:\\\\(a^n)^m=a^{nm}\\\\(ab)^n=a^nb^n\\\\a^2-b^2=(a-b)(a+b)\\\\4x^4yz-16y^3z=4yz(x^2-2y)(x^2+2y)$

6 0

3 years ago

What is solution to <br>12²-5²

expeople1 [14]

Answer:

119.

Step-by-step explanation:

12x12 is 144

5x5 is 25

144-25 = 119

6 0

3 years ago