Theorem itgsin0pi

Description: Calculation of the integral for sine on the (0,π) interval. (Contributed by Glauco Siliprandi, 29-Jun-2017)

	Ref	Expression
Assertion	itgsin0pi	$$⊢{\int }_{\left(0,\mathrm{\pi }\right)}\sin xdx=2$$

Proof

Step	Hyp	Ref	Expression
1		eqid	$$⊢\left(t\in \left[0,\mathrm{\pi }\right]⟼-\cos t\right)=\left(t\in \left[0,\mathrm{\pi }\right]⟼-\cos t\right)$$
2	1	itgsin0pilem1	$$⊢{\int }_{\left(0,\mathrm{\pi }\right)}\sin xdx=2$$