SOLUTION: Give an example of numbers a and b that show {{{sqrt(A + B)}}} is not the same as {{{sqrt(A) + sqrt(B)}}}

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Question 626114: Give an example of numbers a and b that show is not
the same as

Answer by Edwin McCravy(20064)   (Show Source): You can put this solution on YOUR website!
Give an example of numbers a and b that show is not
the same as
Let A = 16, B = 9

 =  = 5

 +  = 4 + 3 = 7

5 does not equal 7.

---------------------------- 

Find all values of a and b that make those two expressions equal to each other.


 = 

Square both sides of the equation:

 = 

 A + B = A + 2 + B

Simplify the equation:

     0 = 2

Divide both sides by 2

     0 = 

Square both sides

    0² = 

     0 = AB

So it's only true if the product of A and B is zero.
That is to say, one or both of A and B must be equal 
to zero.
 
Edwin

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