Question

-6ctg(4π/5)/ctg(π/5)

Answer 1

$frac{- 6 ctg frac{4 pi }{5} }{ctg frac{ pi }{5} } = frac{-6ctg( pi - frac{ pi }{5}) }{ctg frac{ pi }{5} } = frac{6ctg frac{ pi }{5} }{ctg frac{ pi }{5} } = 6$