Simplify the expression 1 cot theta1 cot theta csc2 theta

Simplify the expression. (1 + cot theta)(1 - cot theta) - csc^2 theta -2 cot^2 theta 0 2 2 cot^2 theta

Solution

(1+cot )(1-cot ) - csc² = 1 - cot² - csc²   

= 1 - cot² - (1+cot² ) = 1 - cot² - 1 - cot²

= -2 cot²  (1st option)