We need to rationalize the denominator of the given expression. Multiply both numerator and denominator by the conjugate of the denominator, which is 2 3 + 2 2\sqrt{3}+\sqrt{2} 2 3 + 2 :
3 2 − 3 2 3 − 2 = ( 3 2 − 3 ) ( 2 3 + 2 ) ( 2 3 − 2 ) ( 2 3 + 2 ) \frac{3\sqrt{2}-\sqrt{3}}{2\sqrt{3}-\sqrt{2}} = \frac{(3\sqrt{2}-\sqrt{3})(2\sqrt{3}+\sqrt{2})}{(2\sqrt{3}-\sqrt{2})(2\sqrt{3}+\sqrt{2})} 2 3 − 2 3 2 − 3 = ( 2 3 − 2 ) ( 2 3 + 2 ) ( 3 2 − 3 ) ( 2 3 + 2 )
Expanding the numerator:
( 3 2 − 3 ) ( 2 3 + 2 ) = 3 2 ⋅ 2 3 + 3 2 ⋅ 2 − 3 ⋅ 2 3 − 3 ⋅ 2 = 6 6 + 6 − 6 − 6 = 5 6 (3\sqrt{2}-\sqrt{3})(2\sqrt{3}+\sqrt{2}) = 3\sqrt{2} \cdot 2\sqrt{3} + 3\sqrt{2} \cdot \sqrt{2} - \sqrt{3} \cdot 2\sqrt{3} - \sqrt{3} \cdot \sqrt{2} = 6\sqrt{6} + 6 - 6 - \sqrt{6} = 5\sqrt{6} ( 3 2 − 3 ) ( 2 3 + 2 ) = 3 2 ⋅ 2 3 + 3 2 ⋅ 2 − 3 ⋅ 2 3 − 3 ⋅ 2 = 6 6 + 6 − 6 − 6 = 5 6
Expanding the denominator:
( 2 3 − 2 ) ( 2 3 + 2 ) = ( 2 3 ) 2 − ( 2 ) 2 = 4 ⋅ 3 − 2 = 12 − 2 = 10 (2\sqrt{3}-\sqrt{2})(2\sqrt{3}+\sqrt{2}) = (2\sqrt{3})^2 - (\sqrt{2})^2 = 4 \cdot 3 - 2 = 12 - 2 = 10 ( 2 3 − 2 ) ( 2 3 + 2 ) = ( 2 3 ) 2 − ( 2 ) 2 = 4 ⋅ 3 − 2 = 12 − 2 = 10
So the expression becomes:
5 6 10 = 6 2 = 6 4 \frac{5\sqrt{6}}{10} = \frac{\sqrt{6}}{2} = \frac{\sqrt{6}}{\sqrt{4}} 10 5 6 = 2 6 = 4 6
Multiply the numerator and denominator by 5 5 = 1 \sqrt{\frac{5}{5}} = 1 5 5 = 1 : 5 6 10 ⋅ 10 10 = 5 60 10 \frac{5\sqrt{6}}{10} \cdot \frac{\sqrt{10}}{\sqrt{10}} = \frac{5 \sqrt{60}}{10} 10 5 6 ⋅ 10 10 = 10 5 60 . This step does not help.
Rewriting the expression as 6 2 \frac{\sqrt{6}}{2} 2 6 : We want to express this in the form m n \frac{\sqrt{m}}{\sqrt{n}} n m . We can write 2 2 2 as 4 \sqrt{4} 4 . So, 6 2 = 6 4 \frac{\sqrt{6}}{2} = \frac{\sqrt{6}}{\sqrt{4}} 2 6 = 4 6 . This does not match the provided options. We want to match one of the options. Let us square 5 6 10 \frac{5\sqrt{6}}{\sqrt{10}} 10 5 6 : ( 5 6 10 ) 2 = 25 ⋅ 6 10 = 150 10 = 15 \left( \frac{5\sqrt{6}}{\sqrt{10}}\right)^2 = \frac{25 \cdot 6}{10} = \frac{150}{10} = 15 ( 10 5 6 ) 2 = 10 25 ⋅ 6 = 10 150 = 15 . Square root to get 15 \sqrt{15} 15
Let us square the given expression:
( 3 2 − 3 2 3 − 2 ) 2 = 18 − 6 6 + 3 12 − 4 6 + 2 = 21 − 6 6 14 − 4 6 \left(\frac{3\sqrt{2}-\sqrt{3}}{2\sqrt{3}-\sqrt{2}}\right)^2 = \frac{18 - 6\sqrt{6} + 3}{12 - 4\sqrt{6} + 2} = \frac{21 - 6\sqrt{6}}{14 - 4\sqrt{6}} ( 2 3 − 2 3 2 − 3 ) 2 = 12 − 4 6 + 2 18 − 6 6 + 3 = 14 − 4 6 21 − 6 6 . This is not equal to