[tex]Q = \frac{[a^2(b^2 + c^2) - b^2c^2][b^2(c^2 + a^2) - a^2c^2][c^2(a^2 + b^2) - a^2b^2]}{a^6b^6c^6}[/tex]
[tex] = \frac{(a^2b^2 + a^2c^2 - b^2c^2)(b^2c^2 + a^2b^2 - a^2c^2)(a^2c^2 + b^2c^2 - a^2b^2)}{a^6b^6c^6}[/tex]
[tex]= \frac{a^2b^2 + a^2c^2 - b^2c^2}{a^2b^2c^2} . \frac{b^2c^2 + a^2b^2 - a^2c^2}{a^2b^2c^2} . \frac{a^2c^2 + b^2c^2 - a^2b^2}{a^2b^2c^2}[/tex]
[tex]= (\frac{1}{c^2} + \frac{1}{b^2} - \frac{1}{a^2})(\frac{1}{a^2} + \frac{1}{c^2} - \frac{1}{b^2})(\frac{1}{b^2} + \frac{1}{a^2} - \frac{1}{c^2})[/tex]
[tex]= [\frac{1}{c^2} + (\frac{1}{b} - \frac{1}{a})(\frac{1}{b} + \frac{1}{a})][\frac{1}{a^2} + (\frac{1}{c} - \frac{1}{b})(\frac{1}{c}+ \frac{1}{b}][\frac{1}{b^2} + (\frac{1}{a} - \frac{1}{c})(\frac{1}{a} + \frac{1}{c}][/tex]
[tex]= [\frac{1}{c^2} - \frac{1}{c}(\frac{1}{b} - \frac{1}{a})][\frac{1}{a^2} - \frac{1}{a}(\frac{1}{c} - \frac{1}{a})][\frac{1}{b^2} - \frac{1}{b}(\frac{1}{a} - \frac{1}{c})][/tex]
[tex]= [\frac{1}{c}(\frac{1}{c} - \frac{1}{b} + \frac{1}{a})][\frac{1}{a}(\frac{1}{a} - \frac{1}{c} + \frac{1}{b})][\frac{1}{b}(\frac{1}{b} - \frac{1}{a} + \frac{1}{c})][/tex]
[tex]= \frac{1}{c}. \frac{-2}{b}.\frac{1}{a}.\frac{-2}{c}.\frac{1}{b}.\frac{-2}{a}[/tex]
[tex]= - \frac{8}{a^2b^2c^2}[/tex]
[tex]= - \frac{1}{162}[/tex]
[TẶNG BẠN] TRỌN BỘ Bí kíp học tốt 08 môn
