Find , when

If and -1 < t < 1, prove that

as


Put t = tan




= 2


x = 2() [since, t = sin]


differentiating it with respect to t,


……(1)


Now ,



Put t = tan




= 2


[since t = tan]


differentiating it with respect to t,


……(2)


Dividing equation (2) by (1),




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