SOLUTION: What is the product of the radical expression? (√2+√10) (√2-√10)

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Question 649693: What is the product of the radical expression?
(√2+√10) (√2-√10)
Found 2 solutions by Alan3354, sheldonbbtrocks:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
What is the product of the radical expression?
(√2+√10) (√2-√10)
===================
= 2 - 10
= -8

Answer by sheldonbbtrocks(115) About Me  (Show Source):
You can put this solution on YOUR website!
Well, these two expressions are called conjugates, where they have opposite signs. Use the FOIL method to solve.
To Do this:
sqrt2*sqrt2=2
sqrt2*-sqrt10=-sqrt20
sqrt2*sqrt10=sqrt20
sqrt10*-sqrt10=-10
-sqrt20 and sqrt20 cancel ou.
2-10=-8
The Answer is [-8]