Question 534093
1. Rationalize the denominator. Assume that all expressions under radicals represent positive numbers.
{{{(sqrt(r) - sqrt(s))/(sqrt(r) + sqrt(s))}}}
Multiply NUM and DEN by conjugate of the DEN
= {{{(sqrt(r) - sqrt(s))^2/(r - s))}}}
= {{{(r + s - 2sqrt(rs))/(r - s)}}}
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2. Rationalize the denominator. Assume that all expressions inder radicals represent positive numbers. 
^3Square root of 2y^4
_____________________ (stands for divided by)
^3square root of 6x^4 
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What is ^3 ?
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3. Rationalize the denominator
{{{14sqrt(5)/(5sqrt(2))}}}
= {{{14sqrt(10)/10}}}
= {{{7sqrt(10)/5}}}