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Can you help solve this by simplifying the radical?

Can you help solve this by simplifying the radical?-example-1
User Baksteen
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1 Answer

3 votes

First of all, we can split the root of the multiplication into the multiplication of the roots:


\sqrt[3]{-56ab^6c^(10)}=\sqrt[3]{-56}\cdot\sqrt[3]{a}\cdot\sqrt[3]{b^6}\cdot\sqrt[3]{c^10}

If we look at the prime factorization of -56 we have


-56=2^3\cdot 7

So, we have


\sqrt[3]{-56} = -\sqrt[3]{2^3\cdot 7} = -\sqrt[3]{2^3}\cdot\sqrt[3]{7} = -2\sqrt[3]{7}

We can do nothing about
\sqrt[3]{a}, because the exponent is lower than the order of the root.

We have


\sqrt[3]{b^6} = (b^6)^{(1)/(3)} = b^(6)/(3)=b^2

Finally, we have


\sqrt[3]{c^(10)} =\sqrt[3]{c^(9+1)}=\sqrt[3]{c^(9)\cdot c}=c^(9)/(3)\cdot\sqrt[3]{c}=c^3\sqrt[3]{c}

So, the whole expression is equivalent to


-2b^2c^3\sqrt[3]{7ac}

User Balah
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