SOLUTION: write each rational expression in simplified radical form? square of 2/square of 18

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Question 281390: write each rational expression in simplified radical form? square of 2/square of 18
Found 2 solutions by subudear, Mathematicians:
Answer by subudear(62) About Me  (Show Source):
You can put this solution on YOUR website!
given (2^2)/(18^2)
= 4/324
= 1/81

Answer by Mathematicians(84) About Me  (Show Source):
You can put this solution on YOUR website!
This one is tricky but you want to remember one important property.
If you have sqrt%28a%29%2Fsqrt%28b%29, this is the same thing as sqrt%28a%2Fb%29.
With that general fact in mind, we can see that
sqrt%282%29%2Fsqrt%2818%29+=+sqrt%282%2F18%29
Now we want to simplify the expression inside the square root. 2%2F18+=+1%2F9
sqrt%282%2F18%29+=+sqrt%281%2F9%29
Since the above fact is an equivalence relation, we see the symmetric property that
sqrt%28a%2Fb%29+=+sqrt%28a%29%2Fsqrt%28b%29
so
sqrt%281%2F9%29+=+sqrt%281%29%2Fsqrt%289%29
The easiest way to take the square root of number is to break it up into prime factorizations and remember sqrt(1) = 1
9 is the same thing as 3 * 3
so sqrt%289%29+=+sqrt%283+%2A+3%29+=+3
and sqrt%281%29%2Fsqrt%289%29+=+1%2F3
This was a long explanation of all the work in between, in general, when you do square roots, it's easy to go from one step to the next without showing every detail in between.
For example sqrt%28128%29%2Fsqrt%282%29+=+sqrt%28128%2F2%29+=+sqrt%2864%29+=+8