Prove that:


To Prove:


Formula Used:


1)


2)


Proof:


LHS … (1)




… (2)


Substituting (2) in (1), we get


LHS … (3)


Let


Therefore … (4)



From the figure,


… (5)


From (4) and (5),


… (6)


Substituting (6) in (3), we get


LHS





= tan-1 1



= RHS


Therefore, LHS = RHS


Hence proved.


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