Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

Evaluate the integral.

int-4x^(2)e^(4x)dx
Answer:

Evaluate the integral.\newline4x2e4xdx \int-4 x^{2} e^{4 x} d x \newlineAnswer:

Full solution

Q. Evaluate the integral.\newline4x2e4xdx \int-4 x^{2} e^{4 x} d x \newlineAnswer:
  1. Identify integral: Identify the integral that needs to be solved.\newlineWe need to find the indefinite integral of the function 4x2e4x-4x^2e^{4x} with respect to xx.
  2. Use integration by parts: Use integration by parts.\newlineIntegration by parts formula is udv=uvvdu\int u \, dv = uv - \int v \, du.\newlineLet u=x2u = x^2 (which implies du=2xdxdu = 2x \, dx) and dv=4e4xdxdv = -4e^{4x} \, dx (which implies v=e4xv = -e^{4x}).
  3. Differentiate and integrate: Differentiate uu and integrate dvdv. Differentiating uu gives us du=2xdxdu = 2x \, dx. Integrating dvdv gives us v=e4x4.v = -\frac{e^{4x}}{4}.
  4. Apply integration by parts: Apply the integration by parts formula.\newline4x2e4xdx=uvvdu\int -4x^2e^{4x} dx = uv - \int v du\newline= x2(e4x/4)(e4x/4)(2xdx)x^2(-e^{4x}/4) - \int(-e^{4x}/4)(2x dx)\newline= x2e4x/4+(1/2)xe4xdx-x^2e^{4x}/4 + (1/2)\int xe^{4x} dx
  5. Apply integration by parts again: Apply integration by parts again to the remaining integral.\newlineFor the integral xe4xdx\int x e^{4x} \, dx, let u=xu = x (which implies du=dxdu = dx) and dv=e4xdxdv = e^{4x} dx (which implies v=e4x4v = \frac{e^{4x}}{4}).
  6. Differentiate and integrate: Differentiate uu and integrate dvdv for the second application of integration by parts.\newlineDifferentiating uu gives us du=dxdu = dx.\newlineIntegrating dvdv gives us v=e4x4v = \frac{e^{4x}}{4}.
  7. Apply integration by parts: Apply the integration by parts formula to the remaining integral.\newlinexe4xdx=uvvdu\int x e^{4x} \, dx = uv - \int v \, du\newline= x(e4x4)(e4x4)dxx\left(\frac{e^{4x}}{4}\right) - \int\left(\frac{e^{4x}}{4}\right) \, dx\newline= x(e4x4)(e4x16)+Cx\left(\frac{e^{4x}}{4}\right) - \left(\frac{e^{4x}}{16}\right) + C
  8. Substitute and simplify: Substitute the result from Step 77 back into the equation from Step 44.\newlinex2e4x4+12(x(e4x4)e4x16+C)=x2e4x4+x(e4x)8e4x32+C2- \frac{x^2e^{4x}}{4} + \frac{1}{2}\left(x\left(\frac{e^{4x}}{4}\right) - \frac{e^{4x}}{16} + C\right) = - \frac{x^2e^{4x}}{4} + \frac{x(e^{4x})}{8} - \frac{e^{4x}}{32} + \frac{C}{2}
  9. Substitute and simplify: Substitute the result from Step 77 back into the equation from Step 44.\newlinex2e4x4+12(x(e4x)4e4x16+C)- \frac{x^2e^{4x}}{4} + \frac{1}{2}\left(\frac{x(e^{4x})}{4} - \frac{e^{4x}}{16} + C\right)\newline= x2e4x4+x(e4x)8e4x32+C2- \frac{x^2e^{4x}}{4} + \frac{x(e^{4x})}{8} - \frac{e^{4x}}{32} + \frac{C}{2}Combine the constants and simplify the expression.\newlineThe final answer is the indefinite integral of the given function:\newline4x2e4xdx=x2e4x4+x(e4x)8e4x32+C\int -4x^2e^{4x} dx = - \frac{x^2e^{4x}}{4} + \frac{x(e^{4x})}{8} - \frac{e^{4x}}{32} + C

More problems from Evaluate definite integrals using the chain rule