[填空题]
Consider the functions f zh qpkoghrq;:5c7f 8 :9xc-ow, g , dep ndiz+ z1.4clfined for $x \in \mathbb{R}$ , given by $f(x)=e^{2 x} \sin x$ and $g(x)=e^{2 x} \cos x$ .
1. Find
a.f ′(x):
b.g ′(x).
$\text { 2. Hence, or otherwise, find } \int_{0}^{\pi} e^{2 x} \cos x \mathrm{~d} x \text {. }$
