Which of the following options is NOT a correct trigonometric identity?

Formula used: 

​$$\sin^2\theta + \cos^2 \theta =1 \\ \sec^2 \theta = 1 + \tan^2 \theta \\ 1+\cot^2 \theta = \cosec^2\theta$$​​

Solution: ​

Checking from the options 

option (a) is a  trigonometric identity.

option (b) is a  trigonometric identity. 

option (c) is a trigonometric identity.

derive from $$\sin^2\theta + \cos^2 \theta =1$$​​

option (d) is not a a trigonometric identity 

right identity is $$\sin^2\theta + \cos^2 \theta =1$$ 

therefore, option(d) is correct.

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