What is F(x) = int e^(x-2) - 3x dxF(x)=ex23xdx if F(0) = 1 F(0)=1?

1 Answer
Nov 18, 2016

The function is f(x) = e^(x- 2) - 3/2(x- 2)^2 - 6(x- 2) - 5.135f(x)=ex232(x2)26(x2)5.135, approximately.

Explanation:

Let u = x-2u=x2, then du = dxdu=dx.

=>int(e^u - 3(u + 2))du(eu3(u+2))du

=>int(e^u - 3u - 6)du(eu3u6)du

=>e^u - 3/2u^2 - 6ueu32u26u

We now substitute uu.

=> e^(x - 2) - 3/2(x- 2)^2 - 6(x- 2) + Cex232(x2)26(x2)+C

We know the input/output of the function so we can solve for CC.

When x = 0x=0, y = 1y=1.

1 = e^(0 - 2) - 3/2(0 - 2)^2 - 6(0 - 2) + C1=e0232(02)26(02)+C

1 = e^(-2) - 6 + 12 + C1=e26+12+C

1 - 1/e^2 - 6 = C11e26=C

-5 - 1/e^2 = C51e2=C

C~= -5.135C5.135

Hopefully this helps!