Question

3tgx*ctgx-2cos (π/2+x), если x=0,25

Answer 1

$3tgx*Ctgx-2Cos(\frac{\pi }{2}+x)=3*1+2Sinx=4+2Sinx\\\\4+2Sin0,25\pi=4+2Sin\frac{\pi }{4}=4+2*\frac{\sqrt{2} }{2}=4+\sqrt{2}$