How do you simplify sqrt(49-x^2)49x2?

1 Answer
Jan 31, 2016

This expression cannot be simplified, but it can be re-expressed:

sqrt(49-x^2) = sqrt(7-x)sqrt(7+x)49x2=7x7+x

Explanation:

If a >= 0a0 or b >= 0b0 then sqrt(ab) = sqrt(a)sqrt(b)ab=ab

For any Real number xx, at least one of 7-x >= 07x0 or 7+x >= 07+x0, so we find:

sqrt(49-x^2) = sqrt((7-x)(7+x)) = sqrt(7-x)sqrt(7+x)49x2=(7x)(7+x)=7x7+x