If 3π4<α<π, then cosec2α+2 cot α is equal to
(3)
We have, cosec2α+2cotα
=1+cot2α+2cotα
=|1+cotα|
But 3π4<α<π
⇒ cotα<-1
⇒ 1+cotα<0
Hence, |1+cotα|=-(1+cotα)