一元积分学的应用#
考情分析#
旋转体只考沿坐标轴旋转
几何计算公式#
两类旋转体体积:
$$ 饼状微元:V=\int_a^b\pi[f(x)]^2dx\\ 桶状微元: V=\int_a^b2\pi |x|\cdot |f(x)|dx $$旋转体侧面积:
$$ 饼状微元:S=\int_a^b 2\pi |f(x)|\cdot\sqrt{1+f'^2(x)}dx $$扇形面积:
$$ S=\int_a^b \frac{1}{2}r^2d\theta $$旋转体只考沿坐标轴旋转
两类旋转体体积:
$$ 饼状微元:V=\int_a^b\pi[f(x)]^2dx\\ 桶状微元: V=\int_a^b2\pi |x|\cdot |f(x)|dx $$旋转体侧面积:
$$ 饼状微元:S=\int_a^b 2\pi |f(x)|\cdot\sqrt{1+f'^2(x)}dx $$扇形面积:
$$ S=\int_a^b \frac{1}{2}r^2d\theta $$