Question #042b9

1 Answer
Feb 4, 2017

#f'(x)=(2x)^x(ln(2x)+1)#

Explanation:

#f(x)=(2x)^x#

Take the natural logarithm of both sides:

#ln(f(x))=ln((2x)^x)#

The right-hand side can be rewritten using #ln(a^b)=bln(a)#:

#ln(f(x))=xln(2x)#

Differentiate both sides of the equation. The chain and product rules will be used.

#1/f(x)f'(x)=ln(2x)(d/dxx)+x(d/dxln(2x))#

#1/(2x)^xf'(x)=ln(2x)+x(1/(2x))(d/dx2x)#

#1/(2x)^xf'(x)=ln(2x)+1#

#f'(x)=(2x)^x(ln(2x)+1)#