Problem

Solve the following equation by making an appropriate substitution.
\[
9 x^{\frac{2}{3}}-44 x^{\frac{1}{3}}-5=0
\]
Make an appropriate substitution and rewrite the equation in quadratic form.
Let $u=\square$, then the quadratic equation in $u$ is $\square$.
Solve the equation. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.
A. The solution set is \{\} .
(Type an integer or a simplified fraction. Use a comma to separate answers as needed.)
B. The solution set is the empty set.

Answer

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Answer

Final Answer: The solution set is \(\boxed{\{-\frac{1}{729}, 125\}}\)

Steps

Step 1 :Given the equation \(9 x^{\frac{2}{3}}-44 x^{\frac{1}{3}}-5=0\)

Step 2 :Make an appropriate substitution and rewrite the equation in quadratic form. Let \(u=x^{\frac{1}{3}}\), then the quadratic equation in \(u\) is \(9u^2 - 44u - 5 = 0\)

Step 3 :Solve the quadratic equation for \(u\). The solutions are \(u = -\frac{1}{9}\) and \(u = 5\)

Step 4 :Substitute back to find the value of \(x\). The solutions for \(x\) are \(x = (-\frac{1}{9})^3 = -\frac{1}{729}\) and \(x = 5^3 = 125\)

Step 5 :Final Answer: The solution set is \(\boxed{\{-\frac{1}{729}, 125\}}\)

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