Integration by Parts: To solve the integral of x times the arcsin of x, we can use integration by parts, which is based on the product rule for differentiation and is given by the formula:∫udv=uv−∫vduHere, we can let u=arcsin(x) and dv=xdx. Then we need to find du and v.
Derivative of arcsin(x): First, we differentiate u=arcsin(x) with respect to x to find du. The derivative of arcsin(x) with respect to x is 1−x21. Therefore, du=(1−x21)dx.
Integral of x: Next, we integrate dv=xdx to find v. The integral of x with respect to x is (1/2)x2. Therefore, v=(1/2)x2.
Apply integration by parts: Now we apply the integration by parts formula:∫xarcsin(x)dx=uv−∫vdu= (arcsin(x))(21)x2−∫((21)x2)(1−x21)dx
Simplify the integral: We simplify the integral on the right: ∫(21x2)(1−x21)dx= \frac{\(1\)}{\(2\)}\int\left(\frac{x^\(2\)}{\sqrt{\(1\) - x^\(2\)}}\right) dx
Use substitution: This integral can be tricky, but we can use a substitution to simplify it. Let's use the substitution:\(\newlineLet w=1−x2, then dw=−2xdx.
Solve for xdx: We solve for xdx in terms of dw:xdx=−2dw
Separate and integrate: Substitute w and xdx into the integral: 21∫(1−x2x2)dx = 21∫(w1−w)(−2dw) = −41∫(w1−w)dw
Integrate each term: Now we separate the integral into two parts and integrate each one:−41∫w(1−w)dw= −41∫w1dw+41∫wwdw= -\frac{\(1\)}{\(4\)}\int w^{-\frac{\(1\)}{\(2\)}} dw + \frac{\(1\)}{\(4\)}\int w^{\frac{\(1\)}{\(2\)}} dw)
Combine and substitute: Integrate each term:\(\newline−41∫(w−21)dw=−41(2w21)=−21w41∫(w21)dw=41(32)w23=61w23
Final integral: Combine the two terms and substitute back for w=1−x2:−21w+61w23 = −211−x2+61(1−x2)23
Simplify the expression: Now we have the integral we need to subtract from uv:∫xarcsin(x)dx=(arcsin(x))(21)x2−(−(21)1−x2+(61)(1−x2)23)+C
Simplify the expression: Now we have the integral we need to subtract from uv:∫xarcsin(x)dx=(arcsin(x))(21)x2−(−(21)1−x2+(61)(1−x2)23)+CSimplify the expression:∫xarcsin(x)dx=(21)x2arcsin(x)+(21)1−x2−(61)(1−x2)23+CThis is the final answer in simplified form.
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