What is the partial derivative of f(x,y) with respect to x?

rocomath
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[SOLVED] Partial derivative ... check me please

f(x,y)=\sqrt[5]{x^7y^4}

f_x(x,y)=\frac 1 5(x^7y^4)^{-\frac{4}{5}}(7x^6y^4)

f_x(x,y)=\frac{7x^6y^4}{5\sqrt[5]{x^7y^4}}

Correct?
 
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rocomath said:
f(x,y)=\sqrt[5]{x^7y^4}

f_x(x,y)=\frac 1 5(x^7y^4)^{-\frac{4}{5}}(7x^6y^4)

f_x(x,y)=\frac{7x^6y^4}{5\sqrt[5]{x^7y^4}}

Correct?
I don't think so.

HINT:

f(x,y) = x^{7/5}y^{4/5}
 
Hootenanny said:
I don't think so.

HINT:

f(x,y) = x^{7/5}y^{4/5}
omg ... I'm embarassed :D

ok so ...

f_x(x,y)=\frac 7 5x^{\frac 2 5}y^{\frac 4 5}
 
rocomath said:
omg ... I'm embarassed :D

ok so ...

f_x(x,y)=\frac 7 5x^{\frac 2 5}y^{\frac 4 5}
Sounds good to me :approve:
 
Thanks Hootenanny :)
 
rocomath said:
Thanks Hootenanny :)

A pleasure as always roco :smile:
 
You would have gotten the same answer, but the denominator has the wrong exponent.
 
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