体积=π*(e^x)^2*dx 定积分,积分区间ln2→ln4积分结果：π/2*(e^x)^2 (ln2→ln4)=π/2*[(e^ln4)^2-(e^ln2)^2]=6π(2)体积=π*(x^2)^2*dx 定积分,积分区间1→2积分结果：π/5*x^5 (1→2)=π/5*(2^5-1^5)=π/5*(32-1)=...