SOLUTION: multiply (sqrt11+5sqrt3)(sqrt11-5sqrt3) I just need to know if I am right I thought that the 5sqrt3 would cancel out and I would be left with square root of 11 multiplied by square

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Question 574844: multiply (sqrt11+5sqrt3)(sqrt11-5sqrt3) I just need to know if I am right I thought that the 5sqrt3 would cancel out and I would be left with square root of 11 multiplied by square root of 11 giving me the answer square 121 is this correct?
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
Multiplying as you would for the product of any two binomials you get

The two terms in the middle cancel out and you end up with

Any time you multiply a sum times the difference of the same numbers (or mathematical expressions) there are products that cancel out and you end up with the difference of the squares.
That is usually shown as a "special product" in your book, looking like:
%28a%2Bb%29%28a-b%29=a%5E2-b%5E2
It is very useful for multiplying because you would be able to skip messy intermediate calculations and just write

You use that special product in factoring polynomials, as in
x%5E2-9=%28x%2B3%29%28x-3%29
You can also use it for mental math feats like 48%2A52=2496 because
48%2A52=%2850-2%29%2850%2B2%29=50%5E2-2%5E2=2500-4=2496