\(đka\ge0,b\ge0\\ =\sqrt{a}\left(\sqrt{b}-1\right)-\left(\sqrt{b}-1\right)\\ =\left(\sqrt{a}-1\right)\left(\sqrt{b}-1\right)\)
`ĐK : a >= 0 ; b>=0`
`sqrt{ab} -sqrt{a} -sqrt{b} +1`
`= sqrt{a} ( sqrt{b} -1) - (sqrt{b} -1}`
`= ( sqrt{a} - 1 ) (sqrt{b} - 1)`