Solving a Dumb Math Question: Simplifying Equations with Variables

[Roscoe1989]

Homework Statement

Ok, so I have a=2bc^3 and b= c/f but I want to get rid of the b's.

Homework Equations

So I know I do a=2(c/f)c^3

The Attempt at a Solution

This is where I get lost (and feel stupid). Does this get simplified to (2c^4)/f? Or, is does it stay the same because the (c/f) is in brackets. I have to differentiate after, which is in itself another problem.
Thanks!

 

[berkeman]

Homework Statement

Ok, so I have a=2bc^3 and b= c/f but I want to get rid of the b's.

Homework Equations

So I know I do a=2(c/f)c^3

The Attempt at a Solution

This is where I get lost (and feel stupid). Does this get simplified to (2c^4)/f? Or, is does it stay the same because the (c/f) is in brackets. I have to differentiate after, which is in itself another problem.
Thanks!

The bolded answer is correct. c * c^3 = c^4

 

[Roscoe1989]

Booya! Thank you, berkeman!