The value of (cosec A + cot A + 1)(cosec A − cot A + 1) − 2 cosec A is:
Answer & explanation
Correct answer: option 4
(cosec A + cot A + 1)(cosec A − cot A + 1) − 2 cosec A
Put A = 90º
= (cosec 90º + cot 90º + 1)(cosec 90º − cot 90º + 1) − 2 cosec 90º
= (1 + 0 + 1)(1 − 0 + 1) − 2
= 2