Show that y can be written as a function of x

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SUMMARY

The discussion focuses on demonstrating that the variable y can be expressed as a function of x near the point (0,0) using the equation x³ + y³ = 6x + 2y. By applying the Implicit Function Theorem, it is established that if the partial derivative of y with respect to y (Fy) is non-zero at a specific point, y can indeed be expressed as a function of x. The calculations show that at the point (0,0), Fy equals -2, confirming that y can be written as a function of x in the vicinity of this point. Additionally, the derivative y'(x) is calculated to be -3 at (0,0).

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Homework Statement



Show that y can be written as a function of x near the point (x,y)=(0,0) with

x3+y3=6x+2y and what y'(x) is equal to.

Homework Equations



Implicit Function Theorem

The Attempt at a Solution



By the Implicit Function Theorem, if the partial derivative of y, Fy, does NOT equal 0 at a certain point then y can be

written as a function of x at that certain point.

First, I set the equation to x3+y3-6x-2y=0=F(x,y)

Then I use the formula:

y'(x)=(-Fx)/(Fy)

Thus y'(x)=(-3x2+6)/(3y2-2)

In other words, I am trying to show that the partial derivatives with respect to y

(Fy) does NOT equal zero.

At (0,0), Fy=3(0)2-2= -2

And at y'(0,0)=-3 I am not sure if I applied the Implicit Function Theorem correctly in this problem. Can

anyone see if I miss anything? Remember I ONLY have to show that that y can be

written as a function of x near the point (x,y)=(0,0), nothing less or more.
 
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