Let y = tg(x) be the new variable. Then the given equation takes the form= -2. Multiply by y both sides. You will get = -2y, or = 0, = 0 ---> y+1 = 0. Hence, tg(x) + 1 = 0 ---> tg(x) = -1 ---> x = and/or x = . Answer. There are 2 solutions: x = and/or x = .