`int_(0)^(pi/4)(sec^6xdx)`

int_(0)^( pi/4)sec xdx

int_(0)^( pi/4)sec^(2)xdx

int_0^(pi/4) sec^4xdx

Find the error in steps to evaluate the following integral int_(0)^(pi)(dx)/(1+2 sin ^(2) x )=int _(0)^(pi)(sec^(2)xdx)/(sec^(2)x+2 tan^(2)x)=int_(0)^(pi) (sec^(2)xdx)/(1+3 tan^(2)x) =(1)/(sqrt3)[tan^(-1)(sqrt3 tan x)]_(0)^(pi)=0

int_(0)^( pi/2)sec^(2)xdx

int_(0)^( pi/4)x*sec^(2)xdx=

int_(0)^( pi/4)x*sec^(2)xdx=

int_(0)^(pi//4)(2sec^(2)x+x^(3)+2)dx

I=int_(0)^( pi)*sec^(2)xdx

int_(0)^( pi/2)x sec^(2)xdx