Let f(x)=x+1x2tanx+sinx.
a. (i) Differentiate the numerator N(x)=x2tanx+sinx. Simplify your result.
b. (ii) Differentiate the denominator D(x)=x+1. State the derivative clearly.
c. (iii) Hence obtain f′(x) using an appropriate rule and simplify the final answer so that no factor remains common in the numerator.