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

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To solve for y in the equation 3y^{\frac{2}{3}}=x, first isolate y^{\frac{2}{3}} by dividing both sides by 3, resulting in y^{\frac{2}{3}}=\frac{x}{3}. Next, apply the law of indices to rewrite this as y=\sqrt[\frac{2}{3}]{\frac{x}{3}}, which can also be expressed as y=\sqrt{(\frac{x}{3})^{3}}. To further simplify, cube both sides to obtain y^2=(\frac{x}{3})^3, and then take the square root, leading to y=(\frac{x}{3})^{\frac{3}{2}}. The discussion emphasizes the importance of understanding the laws of indices in manipulating equations.
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3y^{\frac{2}{3}}=x
How do I make y the subject?
y^{\frac{2}{3}}=\frac{x}{3}
Then what?
 
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Hi,
y >= 0
Then
y = \sqrt[\frac{2}{3}]{\frac{x}{3}} = \sqrt{(\frac{x}{3})^{3}}
Hope it help,
Viet Dao,
 
y = \sqrt[\frac{2}{3}]{\frac{x}{3}} = \sqrt{(\frac{x}{3})^{3}}
How did you go from \sqrt[\frac{2}{3}]{\frac{x}{3}} to \sqrt{(\frac{x}{3})^{3}}
 
footprints said:
How did you go from \sqrt[\frac{2}{3}]{\frac{x}{3}} to \sqrt{(\frac{x}{3})^{3}}

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
(\frac{x}{3})^{\frac{3}{2}}=[(\frac{x}{3})^{3}]^{\frac{1}{2}}=\sqrt{(\frac{x}{3})^{3}}

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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