Which one is not an identity tan theta sin thetacos theta s

Which one is not an identity? tan theta = sin theta/cos theta sin^2 theta - cos^2 theta = 1 sec theta = t/cos theta 1 + tan^2 theta = sec^2 theta Which one is not an identify? 1 + cot^2 theta = 1/cos^2 theta csc theta = 1/sin theta sec theta = 1/cos theta tan theta = 1/cot theta Find the quadrant in which theta lies sin theta

Solution

10 . sin²theta - cos²theta=1

According to identity

sin²theta + cos²theta=1

So the given identity is not correct

Hence the correct option is b

11. 1 + cot²theta=1/cos²theta

According to identity

1 + cot²theta=csc²theta=1/sin²theta

So the given identity is not true

Hence the correct option is a

12. sin theta<0 and cot theta <0

sin theta and cot theta are negative in fourth quadrant.

Hence the correct option is d