How do I solve for y in the equation 3y^{\frac{2}{3}}=x?

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Homework Help Overview

The discussion revolves around solving the equation 3y^{\frac{2}{3}}=x for the variable y. Participants explore the manipulation of the equation to isolate y, focusing on the implications of the exponent and the roots involved.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss the steps to isolate y, including taking roots and cubing both sides of the equation. Questions arise regarding the transition between different forms of the equation and the application of exponent laws.

Discussion Status

Several participants have provided insights and clarifications on the manipulation of the equation. There is an ongoing exploration of the mathematical laws applied, with no explicit consensus reached on the final form of y.

Contextual Notes

Participants note the condition that y must be greater than or equal to zero, which may influence the interpretation of the solutions presented.

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[tex]3y^{\frac{2}{3}}=x[/tex]
How do I make y the subject?
[tex]y^{\frac{2}{3}}=\frac{x}{3}[/tex]
Then what?
 
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Hi,
y >= 0
Then
[tex]y = \sqrt[\frac{2}{3}]{\frac{x}{3}} = \sqrt{(\frac{x}{3})^{3}}[/tex]
Hope it help,
Viet Dao,
 
[tex]y = \sqrt[\frac{2}{3}]{\frac{x}{3}} = \sqrt{(\frac{x}{3})^{3}}[/tex]
How did you go from [tex]\sqrt[\frac{2}{3}]{\frac{x}{3}}[/tex] to [tex]\sqrt{(\frac{x}{3})^{3}}[/tex]
 
footprints said:
How did you go from [tex]\sqrt[\frac{2}{3}]{\frac{x}{3}}[/tex] to [tex]\sqrt{(\frac{x}{3})^{3}}[/tex]

Using the law of indicies that says a^mn = (a^m)^n.

y^(2/3) = x/3

Cube both sides: y^2 = (x/3)^3

Now square root both sides: y = (x/3)^3/2 = [(x/3)^3]^1/2, which is what you have (I can't use LaTeX properly, oops).
 
That root in the LHS is another way of writing
[tex](\frac{x}{3})^{\frac{3}{2}}=[(\frac{x}{3})^{3}]^{\frac{1}{2}}=\sqrt{(\frac{x}{3})^{3}}[/tex]

Daniel.
 
Nylex said:
Using the law of indicies that says a^mn = (a^m)^n.

y^(2/3) = x/3

Cube both sides: y^2 = (x/3)^3

Now square root both sides: y = (x/3)^3/2 = [(x/3)^3]^1/2, which is what you have (I can't use LaTeX properly, oops).
Oh ya! Forgot about that. :rolleyes:
Thanks for the help guys!
 

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