Question

rationalise the denominator 3/square root of 7

Answer 1

Multiply by square root of 7 divided by the square root of 7 and this gives you (3 root 7 ) divided by 7.

Answer 2

To do this, we multiply

$3/ \sqrt{7}* \sqrt{7}/ \sqrt{7}$

We can do this be square root 7/square root 7 equals one.  The result of this is:

$3*\sqrt{7}/7$