Simplify $\sqrt[3]{162x^6y^7}$

$\begingroup$

The answer is $3x^2 y^2 \sqrt[3]{6y}$

How does $\sqrt[3]{162x^6y^7}$ equal $3x^2 y^2\sqrt[3]{6y}$?

$\endgroup$ 0

3 Answers

$\begingroup$

\begin{align} \sqrt[3]{162x^6y^7}&=\sqrt[3]{27x^6y^6*6y}\\ &=\sqrt[3]{27x^6y^6}\times\sqrt[3]{6y}\\ &=3x^2y^2\sqrt[3]{6y} \end{align}

$\endgroup$ $\begingroup$

$162x^6y^7=(3x^2y^2)^3\cdot6y$, such that

$$\sqrt[3]{162x^6y^7}=\sqrt[3]{(3x^2y^2)^3\cdot6y}=\sqrt[3]{(3x^2y^2)^3}\sqrt[3]{6y}=3x^2y^2\sqrt[3]{6y}$$

$\endgroup$ $\begingroup$

First note that 162 factors as $2\cdot 3^4$. So collecting our powers of 3 reveals $$\sqrt[3]{162x^6y^7} = \sqrt[3]{3^3 \cdot (x^3)^2\cdot (y^3)^2 \cdot (2\cdot 3 \cdot y)} = 3x^2y^2\sqrt[3]{6y}.$$

$\endgroup$

Your Answer

Sign up or log in

Sign up using Google Sign up using Facebook Sign up using Email and Password

Post as a guest

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

You Might Also Like