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

Limits, differentiation, related rates, integration, trig integrals, etc.
Cafe au lait
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Find the derivative of the function f(x)=-3(2-9x)^(1/4)

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

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

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