" 18."quad (i)int(dx)/(cos(x-a)cos(x-b)),a-b!=n pi,n in Z

int(cos (x-a))/(cos(x-b))dx=

int(cos(x+a)dx)/cos(x+b)

Evaluate the integerals. int (1)/(cos (x-a) cos (x-b))dx on I sub R\\ ({ a +((2n +1)pi )/(2): n in Z}uu{b+ ((2n +1))/(2)pi : n in Z}).

int_0^(pi) (dx)/(a+b cos x) =

I=int_(0)^(2 pi)cos^(-1)(cos x)dx

Q. int_0^pi(e^(cos^2x) cos^3((2n+1) x)) dx, n in I

If int(k)/(cos(x-a)cos(x-b))dx=log[(cos(x-a))/(cos(x-b))]+c , then k=

int_(0)^( pi)(dx)/(a+b cos x)(a>b)