Differentiate `logcosec\ x` from first principal:

Explanation

We have given: `logcosec x`

Let `y=f(x)= logcosecx`br>
Now differentiating w.r.to `x` by using first principle we get

`implies f(x+h)=log cosec(x+h)`

Hence,

`d/(dx)(f(x))=lim_(h->0)(f(x+h)-f(x))/h`

`d/(dx)(f(x))=lim_(h->0)(log cosec(x+h)-logcosecx)/h`

`d/(dx)(f(x))=lim_(h->0)(logsinx-logsin(x+h))/h`

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