Question

ctg²(x-π/2)-ctg(x-3π/2)-2=0

Answer 1

${ctg}^{2} (x - binom{pi}{2} ) - ctg(x - frac{3pi}{2} ) - 2 = 0 \ {tg}^{2} x - tg : x - 2 = 0 \ tg : x = y$
${y}^{2} - y - 2 = 0 \ y = - 1 \ y = 2$
$tg : x = - 1 \ x = pi times n - frac{pi}{4} \ tg : x = 2\ x = pi times n + ctg : 2$