Question

Tg^2x-2tgx-3=0 решение

Answer 1

$tg^2x-2tgx-3=0\\tgx=u\\u^2-2u-3=0\\D: 4+12=16\\u=\frac{2\pm 4}{2}\\\\u_1=3\\tgx=3\\x=arctg3+\pi n, \; n\in Z;\\\\u_2=-1\\tgx=-1\\x=-\frac{\pi}{4}+\pi k, \; k\in Z$