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Question
Show that none of the following is an identity:
`sin^2 theta + sin theta =2`
Solution
`sin^2 theta + sin theta =2`
LHS = `sin^2 theta + sin theta`
=`1- cos^2 theta + sin theta `
=`1- ( cos ^2 theta - sin theta )`
Since LHS ≠ RHS, this is not an identity.
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