SOLUTION: I need so much help on subtracting square roots. The question is : find the differnece of square root of 288 and square root of 72. please help

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Question 15697: I need so much help on subtracting square roots. The question is : find the differnece of square root of 288 and square root of 72. please help
Answer by gsmani_iyer(201) About Me  (Show Source):
You can put this solution on YOUR website!


First of all make the above two square roots into surds as below:
sqrt%28288%29 = sqrt%28144%2A2%29
sqrt%2872%29 = sqrt%2836%2A2%29
Now we have find out the difference between the above 2. Since surds are
irrational numbers, they can be added or subtracted like real numbers. i.e.
sqrt%28144%2A2%29 - sqrt%2836%2A2%29
=12sqrt%282%29 - 6sqrt%282%29
= (12-6)sqrt%282%29
= 6 sqrt%282%29. Answer
The same answer can be written as sqrt%2872%29 by bringing the square of 6
inside the root and multiplying it by 2. In the similar manner, you can do
the additions also.

I hope this is clear to you.

gsm