[问答题]
1. By successive differentiation find the first five non-zer7g+ciozj0/i h o terms in8wkco4 8ld-mo(5wwv p the Maclaurin series fo ow-kp88mov4 5(wcwldr $ f(x)=(2-2 x) \ln (1-x)+2 x$ .
2. Deduce that, for $n \geq 2 $, the coefficient of x^{n} in this series is $\frac{2}{n(n-1)} $.
