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Square root of -15 times square root 5 what is the answer

User VHao
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1 Answer

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The first thing we need to know is that taking the square root of a negative number will result in needing to apply the following rule:

1. The negative sign will turn into an i. This is placed outside of the square root.

2. This results in the following:


\sqrt[]{-15}=i\sqrt[]{15}

Then, we will multiply this by the square root of 5:


i\sqrt[]{15}*\sqrt[]{5}

This can be rationalized:

We can take a 5 out of the 15, leaving a 3. This will also cancel the square root of 5.


5i\sqrt[]{3}

Therefore, this leaves us with our final answer.

User Overthetop
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