Need help. Solve for F(a).Let F(a) be the exact area under the graph of y =(x^2)(e^(−x)) between x = 0 and x = a for a 0.

Question

Need help. Solve for F(a).Let F(a) be the exact area under the graph of y =(x^2)(e^(−x)) between x = 0 and x = a for a > 0.

psymon · Answer

Looks like you would need integration by parts.

anonymous · Answer

i did the general part of that and got (-e^(-x))(x^2+2x+2)

anonymous · Answer

so would the final answer be(-e^(-a))(a^2+2a+2)+2

psymon · Answer

Alright, cool, thats right. Just wanted to check it. So yeah, now it's just F(a) - F(0) and yep, looks like you got it : )

anonymous · Answer

sweet thanks for some reason i kept doing something wrong before. but now when i look at the problem i realized i messed up on the signs....

psymon · Answer

At least its just a small mistake and not a concept misunderstanding. Good job : )

anonymous · Answer

Thanks for the help

psymon · Answer

Mhm. Yw.