How do you rationalize the denominator and simplify sqrt(10/7)?

2 Answers
Jul 9, 2017

sqrt(70)/7

Explanation:

sqrt(10/7)=sqrt(10)/sqrt(7)

To rationalise this denominatir, we multiply the top and bottom by sqrt(7), so we get sqrt(10)/sqrt(7)*sqrt(7)/sqrt(7), sqrt(7)*sqrt(7) is just 7, and sqrt(10)*sqrt(7)=sqrt(10*7)=sqrt(70), as 70 doesn't have any factors which are perfect squares, it can only stay as sqrt(70), giving us sqrt(70)/7

Jul 9, 2017

See the solution process below:

Explanation:

First, we need to rewrite the expression using this rule for dividing radicals:

sqrt(color(red)(a)/color(blue)(b)) = sqrt(color(red)(a))/sqrt(color(blue)(b))

sqrt(color(red)(10)/color(blue)(7)) = sqrt(color(red)(10))/sqrt(color(blue)(7))

Next, we can rationalize the denominator and remove the radical by multiplying the fraction by the appropriate form of 1:

sqrt(7)/sqrt(7) xx sqrt(10)/sqrt(7) = (sqrt(7) xx sqrt(10))/(sqrt(7) xx sqrt(7)) = (sqrt(7) xx sqrt(10))/7

We can now use this rule of exponents to simplify the numerator:

sqrt(color(red)(a)) * sqrt(color(blue)(b)) = sqrt(color(red)(a) * color(blue)(b))

(sqrt(color(red)(7)) * sqrt(color(blue)(10)))/7 = sqrt(color(red)(7) * color(blue)(10))/7 = sqrt(70)/7