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AUFBAL17. [0/2 Points]DETAILSPREVIOUS ANSWERSSimplify.V 125(v5-v7).xNeed Help?Watch ItAdditional MaterialsE eBook

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We are asked to simplify the following expression:


\sqrt[]{125}\cdot(\sqrt[]{5}-\sqrt[]{7})

We can begin with solving the square root of 125.

125 can be expressed as:


125=5\cdot5\cdot5

5 cubed is equal to 125.

Since we have a square root, it is convenient to express that 125 in squares:


125=5^2\cdot5

Then, for the square root of 125:


\sqrt[]{125}=\sqrt[]{5^2\cdot5}

The square root of a product is equivalent to the product of the square roots:


\sqrt[]{125}=\sqrt[]{5^2}\cdot\sqrt[]{5}

We know that the square root of 5 squared is 5:


\sqrt[]{5^2}=5

Then, we can say that:


\sqrt[]{125}=5\cdot\sqrt[]{5}

We can replace the term in the first equation:


\sqrt[]{125}\cdot(\sqrt[]{5}-\sqrt[]{7})=5\cdot\sqrt[]{5}\cdot(\sqrt[]{5}-\sqrt[]{7})

Now, we can solve the parenthesis:


5\cdot\sqrt[]{5}\cdot(\sqrt[]{5}-\sqrt[]{7})=5\cdot\sqrt[]{5}\cdot\sqrt[]{5}-5\cdot\sqrt[]{5}\cdot\sqrt[]{7}

The product of the square roots is equivalent to the square root of the product, then:


\begin{gathered} 5\cdot\sqrt[]{5\cdot5}-5\cdot\sqrt[]{5\cdot7} \\ 5\cdot\sqrt[]{25}-5\cdot\sqrt[]{35} \\ 5\cdot5-5\cdot\sqrt[]{35} \end{gathered}

Finally, the expression simplified will be:


25-5\cdot\sqrt[]{35}

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