SOLUTION: sir what is the root of 5+2*root 6

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Question 969387: sir what is the root of 5+2*root 6

Found 2 solutions by MathTherapy, greenestamps:
Answer by MathTherapy(10801) About Me  (Show Source):
You can put this solution on YOUR website!
sir what is the root of 5+2*root 6
**********************************root of 5 + 2*root 6
I take it, this is: sqrt%285+%2B+2sqrt%286%29%29, the square root of a SURD! If so,
                    sqrt%283+%2B+2+%2B+2sqrt%283%2A2%29%29 ----- Changing 5 to 3 + 2, and 6 (in sqrt%286%29) to 3*2
                    sqrt%283+%2B+2+%2B+2sqrt%283%29sqrt%282%29%29 ------ Applying sqrt%28m%2An%29+=+sqrt%28m%29sqrt%28n%29
  sqrt%28%28sqrt%283%29%29%5E2+%2B+%28sqrt%282%29%29%5E2+%2B+2sqrt%283%29sqrt%282%29%29 ------ Converting 
The above is in the form: %28a+%2B+b%29%5E2, with system%28matrix%282%2C3%2C+a%2C+being%2C+sqrt%283%29%2C+b%2C+being%2C+sqrt%282%29%29%29, and so:
sqrt%28%28sqrt%283%29%29%5E2+%2B+%28sqrt%282%29%29%5E2+%2B+2sqrt%283%29sqrt%282%29%29 then becomes: sqrt%28%28sqrt%283%29+%2B+sqrt%282%29%29%5E2%29 
                                                                               highlight%28sqrt%283%29+%2B+sqrt%282%29%29 ----- Cancelling SQUARE and SQUARE ROOT

Answer by greenestamps(13325) About Me  (Show Source):
You can put this solution on YOUR website!


Consider this:

%28sqrt%28x%29%2Bsqrt%28y%29%29%5E2=%28x%2By%29%2B2sqrt%28xy%29

In the form on the right, the rational part is the sum of two integers and the expression under the radical is the product of those two integers, and there is a multiplier "2" outside the radical.

In your problem, you are to find

sqrt%285%2A2sqrt%286%29%29

This is in the form of the pattern above: 5 is the sum of 2 and 3; 6 is the product of 2 and 3; and the radical has a multiplier "2". So the problem fits the pattern:

sqrt%285%2B2sqrt%286%29%29=sqrt%283%29%2Bsqrt%282%29

Here are a couple of random examples to help you see the pattern:

sqrt%2817%2B2sqrt%2870%29%29=sqrt%2810%29%2Bsqrt%287%29 [17 is 10+7; 70 is 10*7]

sqrt%289%2B2sqrt%2814%29%29=sqrt%287%29%2Bsqrt%282%29 [9 is 7+2; 14 is 7*2]

ANSWER: sqrt%285%2B2sqrt%286%29%29=sqrt%283%29%2Bsqrt%282%29