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Evaluate `int xsin^(2)x dx` |
Answer» Correct Answer - `(1)/(4)x^(2)-(x)/(4)sin2x-(1)/(8)cos 2x+C` `int xsin^(2)x dx` `=int x{(1-cos2x)/(2)}dx=(1)/(2)intxdx-(1)/(2)int underset(I)(x)underset(II)(cos)2x dx` `=(1)/(2)((x^(2))/(2))-(1)/(2)[x{intcos 2x dx}-int{(d)/(dx)(x)int cos2x}dx]` `=(1)/(4)x^(2)-(1)/(2){(x)/(2)sin2x-int1xx(sin2x)/(2)dx}` `=(x^(2))/(4)-(1)/(2){(x)/(2)sin 2x-(1)/(2)int sin2xdx}` `=(x^(2))/(4)-(1)/(2){(x)/(2)sin 2x-(1)/(2)(-(1)/(2)cos2x)}+C` `=(1)/(4)x^(2)-(x)/(4)sin2x-(1)/(8)cos 2x+C` |
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