Question

решите пожалуйста.25б

Answer 1

$Ctgx<-1\\\\arcCtg(-1)+\pi n<x<\pi+\pi n,n\in Z\\\\\frac{3\pi }{4}+\pi n<x<\pi+\pi n,n\in Z\\\\x\in(\frac{3\pi }{4} +\pi n,\pi+\pi n),n\in Z$

Answer 2

$ctgx<-1\\\\\frac{3\pi }{4}+\pi n<x<\pi +\pi n\; ,\; n\in Z$