Skip to main contentSkip to solution

∫e2x(sin⁡x+12cos⁡x)dx\int e^{2x}(\sin x + \frac{1}{2}\cos x) dx is equal to

Solution

✅ Correct Option: 2

When integrating eaxe^{ax} multiplied with a combination of sin⁡x\sin x and cos⁡x\cos x, the result typically has the form eaxe^{ax} times another trigonometric combination.

For this integral, consider the function 12e2xsin⁡x\frac{1}{2}e^{2x}\sin x.


To check if this is correct, differentiate 12e2xsin⁡x\frac{1}{2}e^{2x}\sin x using the product rule:

ddx[12e2xsin⁡x]\frac{d}{dx}\left[\frac{1}{2}e^{2x}\sin x\right]

=12[(e2x)′⋅sin⁡x+e2x⋅(sin⁡x)′]= \frac{1}{2}\left[(e^{2x})' \cdot \sin x + e^{2x} \cdot (\sin x)'\right]

=12[2e2x⋅sin⁡x+e2x⋅cos⁡x]= \frac{1}{2}\left[2e^{2x} \cdot \sin x + e^{2x} \cdot \cos x\right]

=e2xsin⁡x+12e2xcos⁡x= e^{2x}\sin x + \frac{1}{2}e^{2x}\cos x

=e2x(sin⁡x+12cos⁡x)= e^{2x}\left(\sin x + \frac{1}{2}\cos x\right)

This matches the integrand exactly.


Therefore:

∫e2x(sin⁡x+12cos⁡x)dx=12e2xsin⁡x+C\int e^{2x}\left(\sin x + \frac{1}{2}\cos x\right) dx = \frac{1}{2}e^{2x}\sin x + C

Keyboard Shortcuts

  • Left arrow: Previous question
  • Right arrow: Next question
  • S key: Jump to solution
  • Q key: Jump to question