Question

Rationalize the denominator and simplify.

Answer 1

\[\sqrt{7}=2.64\]

Answer 2

2.64575131 to be exact

Answer 3

\[\frac{ 12 }{ \sqrt{7}+2 }\]To rationalize this, multiply the fraction by \[\frac{ \sqrt{7}-2 }{ \sqrt{7}-2 }\]This ensures that the value of the expression stays the same, but the denominator will not contain any radicals. (Notice how I multiplied by sqrt(7) MINUS two; this is a difference of squares.)