Recognize the integral: Recognize the integral to be solved.We need to find the integral of earcsinx with respect to x, which is written as ∫earcsinxdx.
Use substitution to simplify: Use substitution to simplify the integral.Let u=arcsinx, which implies that x=sinu. Then, we need to find dx in terms of du. Since u=arcsinx, we differentiate both sides with respect to x to get dxdu=1−x21. Therefore, dx=1−x2du.
Substitute x and dx: Substitute x and dx in the integral.The integral becomes ∫eu1−sin2udu. Since sin2u+cos2u=1, we have 1−sin2u=cosu. So the integral simplifies to ∫eucosudu.
Use integration by parts: Use integration by parts.Integration by parts states that ∫udv=uv−∫vdu. We let u=eu and dv=cosudu. Then du=eudu and v=sinu. Applying integration by parts gives us eu⋅sinu−∫sinu⋅eudu.
Apply integration by parts again: Apply integration by parts again to the remaining integral.We need to integrate ∫sinu⋅eudu. Let's use integration by parts again with u=sinu and dv=eudu. Then du=cosudu and v=eu. This gives us sinu⋅eu−∫eu⋅cosudu.
Notice the repeating integral: Notice the repeating integral. We see that ∫eu⋅cosudu appears again. Let's call this integral I. Our equation from Step 4 and Step 5 becomes eu⋅sinu−(sinu⋅eu−I), which simplifies to eu⋅sinu−sinu⋅eu+I=I.
Solve for I: Solve for I.We have I=eu⋅sinu−sinu⋅eu+I. Subtracting I from both sides, we get 0=eu⋅sinu−sinu⋅eu, which implies that I=eu⋅sinu.
Substitute back in terms of x: Substitute back in terms of x.We originally let u=arcsinx, so we substitute back to get I=earcsinx⋅sin(arcsinx). Since sin(arcsinx)=x, our integral I=earcsinx⋅x.
Add the constant of integration: Add the constant of integration.The final answer is I=earcsinx⋅x+C, where C is the constant of integration.
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