What is the derivative of 2axe^-2bx

Assume a and b are constants

a + b = c brah

If a and b are constants, then it looks like a product rule combined with a chain rule.

treat (2ax) as one term, and (e^(-2bx)) as the other term.

then product rule these 2 terms:
= (2ax)*d/dx(e^(-2bx)) + (e^(-2bx))*d/dx(2ax)

now you see the bolded part above needs to be chain-ruled:

= (2ax)*(e^(-2bx))*(-2b) + (e^(-2bx))*(2a)

now the product rule and chain rule have been applied, and all the derivatives are taken care of. All that remains is to combine like terms and simplify. I'll leave that to you.

maybe this is easier to follow than the above post.