Thursday, December 3, 2015

Given the integrals A and B, find A+B? A=Integral x*cos^2 xdx B = Integral x*sin^2x dx

We have the integrals A and B defined as A = Int[x*(cos x)^2
dx]


and B = Int[x*(sin x)^2 dx]


A +
B


=> Int[x*(cos x)^2 dx] + Int[x*(sin x)^2
dx]


=> Int[x*(cos x)^2 + x*(sin x)^2
dx]


=> Int[x*((cos x)^2 + (sin x)^2)
dx]


use the property that (sin x)^2 + (cos x)^2 =
1


=> Int[x dx]


=> x^2 / 2
+ C


The value of A + B = x^2/2 +
C

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