If `x=asint\ ` and `y=a(cost+logtan(t/2))` , find `(d^2\ y)/(dx^2)`

Explanation

`x = asint`

`=>dx/dt = acost`

`y = a(cost+logtan(t/2))`

`=>dy/dt = a(-sint+1/tan(t/2)(1/2sec^2(t/2)))`

`=>dy/dt = a(-sint + 1/(2sin (t/2)cos (t/2)))`

`=>dy/dt = a(-sint + 1/sint)`

`=>dy/dt = a((1-sin^2t)/sint)`

`=>dy/dt = a(cos^2t/sint)`

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