Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

Evaluate the integral.

int4xe^(-3x+1)dx
Answer:

Evaluate the integral.\newline4xe3x+1dx \int 4 x e^{-3 x+1} d x \newlineAnswer:

Full solution

Q. Evaluate the integral.\newline4xe3x+1dx \int 4 x e^{-3 x+1} d x \newlineAnswer:
  1. Rewrite Integral: Let's first rewrite the integral to make it clearer:\newline4xe(3x+1)dx\int 4xe^{(-3x+1)}dx\newlineWe can treat the constant term e1e^1 as a constant multiplier, which can be taken out of the integral. So we rewrite the integral as:\newline4exe(3x)dx4e \cdot \int xe^{(-3x)}dx\newlineNow we need to apply integration by parts, where we let u=xu = x (which will be differentiated) and dv=e(3x)dxdv = e^{(-3x)}dx (which will be integrated).
  2. Integration by Parts: Differentiate u=xu = x to get du=dxdu = dx. Integrate dv=e3xdxdv = e^{-3x}dx to get vv. To integrate e3xe^{-3x}, we use the fact that the integral of eaxe^{ax} is (1/a)eax(1/a)e^{ax}, so the integral of e3xe^{-3x} is (1/3)e3x(-1/3)e^{-3x}. Therefore, v=(1/3)e3xv = (-1/3)e^{-3x}.
  3. Substitute uu, dudu, vv: Now apply the integration by parts formula:\newlineudv=uvvdu\int u\,dv = uv - \int v\,du\newlineSubstitute uu, dudu, vv into the formula:\newlinexe3xdx=x(13)e3x(13)e3xdx\int x e^{-3x}\,dx = x\left(-\frac{1}{3}\right)e^{-3x} - \int \left(-\frac{1}{3}\right)e^{-3x}\,dx
  4. Integrate (13)e3xdx\int(-\frac{1}{3})e^{-3x}\,dx: Now we need to integrate (13)e3xdx\int(-\frac{1}{3})e^{-3x}\,dx. As before, the integral of e3xe^{-3x} is (13)e3x(-\frac{1}{3})e^{-3x}, so we get:\newline(13)e3xdx=(13)(13)e3x=(19)e3x\int(-\frac{1}{3})e^{-3x}\,dx = (-\frac{1}{3})\cdot(-\frac{1}{3})e^{-3x} = (\frac{1}{9})e^{-3x}
  5. Substitute back into formula: Substitute this result back into the integration by parts formula:\newlinexe3xdx=x(13)e3x(19)e3x\int xe^{-3x}dx = x*(-\frac{1}{3})e^{-3x} - (\frac{1}{9})e^{-3x}\newlineNow we multiply through by the constant 4e4e from the original integral:\newline4e(x(13)e3x(19)e3x)4e * (x*(-\frac{1}{3})e^{-3x} - (\frac{1}{9})e^{-3x})
  6. Simplify the expression: Simplify the expression:\newline4e(x(13)e3x(19)e3x)=(4e3)(x)e3x(4e9)e3x4e \cdot (x\cdot(-\frac{1}{3})e^{-3x} - (\frac{1}{9})e^{-3x}) = (\frac{4e}{3})(-x)e^{-3x} - (\frac{4e}{9})e^{-3x}\newlineNow we add the constant of integration CC to get the final result:\newline(4e3)(x)e3x(4e9)e3x+C(\frac{4e}{3})(-x)e^{-3x} - (\frac{4e}{9})e^{-3x} + C