Wednesday
April 1, 2015

Homework Help: maths

Posted by Candice on Friday, October 19, 2012 at 9:35am.

by equating the coefficients of sin x and cos x , or otherwise, find constants A and B satisfying the identity.

A(2sinx + cosx) + B(2cosx - sinx) = sinx + 8cosx

I got A = 2, B = 3, which the answers said were correct.

However, another part of the question asked

hence integrate

sinx + 8cosx
-------------dx
2sinx + cosx


and the answers were 2x + 3Ln (2sinx + cosx) + C

Could you explain how to get this?

Thanks in advance !!! :)

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