identities

[carlasader]

please try to help me solve it

 

[skeeter]

so ... what have you accomplished on your own?

 

[stapel]

For those who may not be able to view the image (which contains just text) or be able to read the fuzzier bits of the image, the exercise appears to be as follows:

a) Use the identities for cos(A + B) and cos(A - B) to prove that:

. . .i) 2 cos(A) cos(B) = cos(A + B) + cos(A - B)

. . .ii) cos^2(A) = (1/2)(1 + cos(2A))

b) Find the indefinite integral: int [ cos(3x) cos(x) ] dx

c) Use the substitution "x = cos(t)" to evaluate the definite integral:

. . .int [0 to 1/2] [ x^2 / (1 - x^2)^(1/2) ] dx

To the original poster: Kindly please reply with corrections or confirmation. When you reply, please include a clear listing of everything you have tried so far.

Thank you!

Eliz.

 

[o_O]

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