Prove that:



To Prove:


Formula Used:


Proof:


LHS … (1)


Let x = tan A … (2)


Substituting (2) in (1),


LHS


= tan-1 (tan 3A)


= 3A


From (2), A = tan-1 x,


3A = 3 tan-1 x


= RHS


Therefore, LHS = RHS


Hence proved.


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