Q20 of 48 Page 84

Prove the following with the help of identities:

Taking L.H.S we get,



⇒


⇒


Taking L.C.M and using: a3 – b3 = (a – b)(a2 + b2 + ab)


⇒


⇒


⇒


⇒ cot θ + tan θ + 1


⇒ +1


⇒ + 1


⇒ cosec θ.sec θ + 1


= R.H.S


Hence, proved.


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