" 14."(1-cos x)/(cos x^(3)(1+cos x))

int(1-cos x)/(cos x(1+cos x))dx

underset(x to π/2)"Lt" ((1+cos x)/(1-cos x))^(1//cos x)=

(cos3x-cos x)/(cos x+cos3x)

logsqrt((1-cos x)/(1+cos x))

logsqrt((1-cos x)/(1+cos x))

int(cos x-cos2x)/(1-cos x)*dx

tan^(-1){(sqrt(1+cos x)+sqrt(1-cos x))/(sqrt(1+cos x)-sqrt(1-cos x))}

Simplest form of tan^(-1)((sqrt(1+cos x)+sqrt(1-cos x))/(sqrt(1+cos x)-sqrt(1-cos x))), pi lt x lt (3 pi)/(2) is: