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How do I go about solving for $x$ in this equation?

$$\displaystyle -x^{-\large\frac{3}{4}} + \frac{15^{\large\frac{1}{4}}}{15} = 0$$

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I've edited for formatting --- please check to see that I got it right. –  Gerry Myerson Feb 18 '13 at 23:40
    
You had it right @Gerry. Then it was edited after your edit using teeny-tiny fractional exponents. So I made them larger. –  amWhy Feb 18 '13 at 23:48

1 Answer 1

Hint: $$-x^{-3/4} + \frac{15^{1/4}}{15} = 0 \iff -\frac {1}{x^{3/4}} + \frac{15^{1/4}}{15^{4/4}} = 0$$

$$\iff -\frac {1}{x^{3/4}} + \frac{1}{15^{3/4}} = 0$$

$$\iff \dfrac{x^{3/4}}{15^{3/4}} = 1 \iff \left(\frac{x}{15}\right)^{3/4} = 1$$

Can you take it from here?

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its 15! Thanks! –  user62885 Feb 18 '13 at 23:43
    
Yes, your correct! You're welcome! –  amWhy Feb 18 '13 at 23:45

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