Practicing Success
If $(5\sqrt{5}x^3-3\sqrt{3}y^3)÷ (\sqrt{5}x-\sqrt{3}y) = (Ax^2 + By^2+Cxy)$, then the value of $(3A+B - \sqrt{15}C)$ is: |
8 5 3 12 |
3 |
( a - b ) = \(\frac{a^3 - b^3}{a^2 + b^2 + ab }\) If $(5\sqrt{5}x^3-3\sqrt{3}y^3)÷ (\sqrt{5}x-\sqrt{3}y) = (Ax^2 + By^2+Cxy)$ On comparing the above equation with ( a - b ) = \(\frac{a^3 - b^3}{a^2 + b^2 + ab }\) we can conclude that , a = ($ \sqrt{5}$)2 = 5 b = ($\sqrt{3}$)2 = 3 c = $ \sqrt{5}$ × $\sqrt{3}$ = \(\sqrt {15}\) So, put them in $(3A+B - \sqrt{15}C)$ = 3 × 5 + 3 -(\(\sqrt {15}\) × \(\sqrt {15}\)) = 18 - 15= 3 |