[问答题]
1. By successive differ176 n 6klotdm: . ;beojzdsk)e s6v3ur5ss-sf entiation find the first five non-zero terms in the Maclaurin series for u5-s frs3v6ss $ 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)} $.
