定積分・広義積分計算機
定積分と広義積分を手順を追って計算する
この計算機は、定積分(すなわち上下限のある積分)を、広義積分も含めて、解法手順を示しながら計算を試みます。
Solution
Your input: calculate $$$\int_{0}^{2}\left( \pi \sin{\left(x \right)} \right)dx$$$
First, calculate the corresponding indefinite integral: $$$\int{\pi \sin{\left(x \right)} d x}=- \pi \cos{\left(x \right)}$$$ (for steps, see indefinite integral calculator)
According to the Fundamental Theorem of Calculus, $$$\int_a^b F(x) dx=f(b)-f(a)$$$, so just evaluate the integral at the endpoints, and that's the answer.
$$$\left(- \pi \cos{\left(x \right)}\right)|_{\left(x=2\right)}=- \pi \cos{\left(2 \right)}$$$
$$$\left(- \pi \cos{\left(x \right)}\right)|_{\left(x=0\right)}=- \pi$$$
$$$\int_{0}^{2}\left( \pi \sin{\left(x \right)} \right)dx=\left(- \pi \cos{\left(x \right)}\right)|_{\left(x=2\right)}-\left(- \pi \cos{\left(x \right)}\right)|_{\left(x=0\right)}=- \pi \cos{\left(2 \right)} + \pi$$$
Answer: $$$\int_{0}^{2}\left( \pi \sin{\left(x \right)} \right)dx=- \pi \cos{\left(2 \right)} + \pi\approx 4.44895649810093$$$