Question

решите уравнения (х^2+2х)^2-7(х^2+2х)-8=0

Answer 1

x^2+2x=t,t^2-7t-8=0,t1=-1,t2=8;1)x^2+2x+1=0,x=-1;x^2+2x-8=0,x=-4,x=2