Question

How do you integrate 7xe^-5x²?

Answer 1

Making assumptions about where parentheses should be, 
Let u = -7x 
du = -7dx 
dv = e^(2x) dx 
v = e^(2x)/2 
∫ -7xe^(2x) dx = 
-7xe^(2x)/2 - ∫ e^(2x)/2 (-7) dx = 
-7xe^(2x)/2 + 7e^(2x)/4 + c