What is F(x) = int sin(3x)-sinxcos^2(4x) dxF(x)=sin(3x)sinxcos2(4x)dx if F(pi) = 3 F(π)=3?

1 Answer
Apr 28, 2017

F(x) =1/2cosx-1/3cos3x-1/28cos7x+1/36cos9x+199/63F(x)=12cosx13cos3x128cos7x+136cos9x+19963

Explanation:

F(x) = int sin3x - sinxcos^2(4x)dx=F(x)=sin3xsinxcos2(4x)dx=
1/2cosx-1/3cos3x-1/28cos7x+1/36cos9x+"c"12cosx13cos3x128cos7x+136cos9x+c

F(pi)= -10/63 + "c"=3F(π)=1063+c=3

"c"=199/63c=19963

F(x) =1/2cosx-1/3cos3x-1/28cos7x+1/36cos9x+199/63F(x)=12cosx13cos3x128cos7x+136cos9x+19963