The integral ∫–13/2(|π2xsin(πx)|)dx is equal to : [2025]
(3)
Let I=∫–13/2|π2xsinπx|dx
=π2[∫–11xsinπxdx–∫13/2xsinπxdx]
=π2[2∫01xsinπxdx–∫13/2xsinπxdx]
=π2[2[–xcosπxπ+sinπxπ2]01–[–xcosπxπ+sinπxπ2]13/2]
=π2[2π–(–1π2–1π)]=π2[3π+1π2]
=3π+1.