What is the first derivative of a complex surge function?

this is the complex surge function #y=kx^a e^(-bx)# where a, b, k are positive constants.

1 Answer
Apr 14, 2018

#y'(x)=akx^(a-1)e^(-bx)-bkx^a*e^(-bx)#

Explanation:

use the product rule
[#d/dx(f(x)g(x))=f'(x)g(x)+f(x)g'(x)#]

#y'(x)=d/dx(kx^a)*(e^(-bx))+kx^a*d/dx(e^(-bx))#
#y'(x)=akx^(a-1)e^(-bx)+kx^a*e^(-bx)(-b)#
#y'(x)=akx^(a-1)e^(-bx)-bkx^a*e^(-bx)#

could also equal:
#y'(x)=kx^(a-1)e^(-bx)(a-bx)#