The expression $(cos^6\theta + sin^6\theta - 1) (tan^2\theta +cot^2\theta +2) +3 $ is equal to :
Answer & explanation
Correct answer: option 1
( cos6θ + sin6θ - 1 ) ( tan2θ + cot2θ + 2 ) + 3
Put θ = 45º
= ( cos645º+ sin645º - 1 ) ( tan245º + cot245º + 2 ) + 3
= ( \(\frac{1}{8}\) + \(\frac{1}{8}\) - 1 ) ( 1 + 1 + 2 ) + 3
= - \(\frac{3}{4}\) × 4 + 3
= 0