Find the derivative of the function f(x)=-3(2-9x)^(1/4)

Limits, differentiation, related rates, integration, trig integrals, etc.
Cafe au lait
Posts: 6
Joined: Mon Jan 03, 2011 11:02 pm
Contact:

Find the derivative of the function f(x)=-3(2-9x)^(1/4)

Postby Cafe au lait » Mon Jan 03, 2011 11:22 pm

Find the derivative of the function f(x)=-3(2-9x)^(1/4)

I have:

f'(x)=-3[1/4(2-9x)(-9)]+0(2-9x)^(1/4)
=-3[-9/4(2-9x)]
=-3(81/4x-9/2)
=-243/4x+27/2

Did I do that right?

nona.m.nona
Posts: 262
Joined: Sun Dec 14, 2008 11:07 pm
Contact:

Re: Find the derivative of the function f(x)=-3(2-9x)^(1/4)

Postby nona.m.nona » Mon Jan 03, 2011 11:58 pm

Cafe au lait wrote:Find the derivative of the function f(x)=-3(2-9x)^(1/4)

I have:

f'(x)=-3[1/4(2-9x)(-9)]+0(2-9x)^(1/4)

When you took the 1/4 power down front, what should have been left behind as the power on the parenthetical?

Cafe au lait
Posts: 6
Joined: Mon Jan 03, 2011 11:02 pm
Contact:

Re: Find the derivative of the function f(x)=-3(2-9x)^(1/4)

Postby Cafe au lait » Tue Jan 04, 2011 2:16 am

Lol I redid it without the product rule and that made it a lot easier! I know I got it right now, thanks! :)


Return to “Calculus”