Question 101948
Rationalize the denominator:
square root of x - the square root of y
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square root of x + the square root of y
:
Multiply it by the conjugate of the denominator over itself:
{{{(sqrt(x) - sqrt(y))/(sqrt(x) + sqrt(y))}}} * {{{(sqrt(x) - sqrt(y))/(sqrt(x) - sqrt(y))}}} = {{{(x - sqrt(xy) - sqrt(xy) + y)/(x - sqrt(xy) + sqrt(xy) - y)}}} = {{{(x - 2*sqrt(xy) + y)/(x - y)}}}