Question

Find the exact value of the expression

Answer 1

Of what expression?

Answer 2

In order to get an exact result, you can only add those radical expression that have the same number under the sign of the radical,
\[4\sqrt{13}-7\sqrt{13}+\sqrt{6}=-3\sqrt{13}+\sqrt{6}\]

Answer 3

the answer would be: -3√13+√6