3.31: Derivative of a quotient, small change, and ln integral

0606/22/M/J/23 — Question 7 · 12 marks

(a)
Given f(x)=3x+42x5f(x) = \dfrac{3x + 4}{2x - 5} for x52x \neq \dfrac{5}{2}, find f(x)f'(x) as a simplified algebraic fraction.
[3]
(b)
Variables xx and yy are related by y=3x+2x+5y = 3x + \dfrac{2}{x} + 5. Using differentiation, find the approximate change in xx when yy increases from 1010 by 0.010.01.
[4]
(c)(i)
Differentiate y=x3lnxy = x^{3}\ln x with respect to xx.
[2]
(c)(ii)
Hence find (6x2lnx+2x2)dx\displaystyle\int (6x^{2}\ln x + 2x^{2})\,\mathrm{d}x.
[3]