what is sqrt(7+sqrt29) * sqrt(7-sqrt29)??

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by sureshbala » Mon Feb 09, 2009 3:17 pm
I guess you want to know the value of sqrt[7+sqrt(29)] x sqrt[7-sqrt(29)]

We have sqrt(a+b) x sqrt(a-b) = sqrt(a^2-b^2)
= sqrt(49-29) = sqrt(20)= 2 sqrt(5)

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by ellexay » Wed Feb 11, 2009 6:17 pm
What's the OA?

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by ven4gmat » Thu Feb 12, 2009 1:47 am
The answer must be sqrt(20). What is the OA?