$\begin{array}{1 1}(a)\;x_1-\large\frac{a^2}{x_1},\normalsize (e^2-1)x_1\\(b)\;x_1-\large\frac{a}{x_1},\normalsize (e^3-1)x_1\\(c)\;x_1^2+\large\frac{a^2}{x_1},\normalsize (e-1)x_1\\(d)\;x_1+\large\frac{a^2}{x_1},\normalsize (e^2+1)x_1\end{array}$
