Question

sec squared theta +cot square ninety minus theta - 2 cosec square theta = - 1

Answer 1

LHS=
sec^2 theta + cot ^2 (90- theta) - 2 cosec^2 theta
=sec^2 thera + tan^2 theta - 2 cosec^2 theta
=1/cos^2 theta + sin^2 theta/ cos^2 theta - (2* 1/sin^2 theta)
=1+sin^2 theta/cos^2 theta - 2/sin^2 theta
=1+sin^2theta *-2cos^2 theta/sin^2 theta*cos^2 theta
=1+(-2)
=-1