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Question Number 63291 by aliesam last updated on 02/Jul/19
find some of all real x such that    ((4x^2 +15x+17)/(x^2 +4x+12)) = ((5x^2 +16x+18)/(2x^2 +5x+13))
$${find}\:{some}\:{of}\:{all}\:{real}\:{x}\:{such}\:{that} \\ $$$$ \\ $$$$\frac{\mathrm{4}{x}^{\mathrm{2}} +\mathrm{15}{x}+\mathrm{17}}{{x}^{\mathrm{2}} +\mathrm{4}{x}+\mathrm{12}}\:=\:\frac{\mathrm{5}{x}^{\mathrm{2}} +\mathrm{16}{x}+\mathrm{18}}{\mathrm{2}{x}^{\mathrm{2}} +\mathrm{5}{x}+\mathrm{13}} \\ $$
Commented by Prithwish sen last updated on 02/Jul/19
((2x^2 +5x+13)/(x^2 +4x+12)) = ((5x^2 +16x+18)/(4x^2 +15x+17))  ((x^2 +x+1)/(x^2 +4x+12)) = ((x^2 +x+1)/(4x^2 +15x+17))  either x^2 +x+1=0  or 4x^2 +15x+17−x^2 −4x−12 =0  3x^2 +11x+5=0  ∴ x = ((−1±(√(−3)))/2) , ((−11±(√(61)))/6)  please check
$$\frac{\mathrm{2x}^{\mathrm{2}} +\mathrm{5x}+\mathrm{13}}{\mathrm{x}^{\mathrm{2}} +\mathrm{4x}+\mathrm{12}}\:=\:\frac{\mathrm{5x}^{\mathrm{2}} +\mathrm{16x}+\mathrm{18}}{\mathrm{4x}^{\mathrm{2}} +\mathrm{15x}+\mathrm{17}} \\ $$$$\frac{\mathrm{x}^{\mathrm{2}} +\mathrm{x}+\mathrm{1}}{\mathrm{x}^{\mathrm{2}} +\mathrm{4x}+\mathrm{12}}\:=\:\frac{\mathrm{x}^{\mathrm{2}} +\mathrm{x}+\mathrm{1}}{\mathrm{4x}^{\mathrm{2}} +\mathrm{15x}+\mathrm{17}} \\ $$$$\mathrm{either}\:\mathrm{x}^{\mathrm{2}} +\mathrm{x}+\mathrm{1}=\mathrm{0} \\ $$$$\mathrm{or}\:\mathrm{4x}^{\mathrm{2}} +\mathrm{15x}+\mathrm{17}−\mathrm{x}^{\mathrm{2}} −\mathrm{4x}−\mathrm{12}\:=\mathrm{0} \\ $$$$\mathrm{3x}^{\mathrm{2}} +\mathrm{11x}+\mathrm{5}=\mathrm{0} \\ $$$$\therefore\:\mathrm{x}\:=\:\frac{−\mathrm{1}\pm\sqrt{−\mathrm{3}}}{\mathrm{2}}\:,\:\frac{−\mathrm{11}\pm\sqrt{\mathrm{61}}}{\mathrm{6}} \\ $$$$\mathrm{please}\:\mathrm{check} \\ $$$$ \\ $$$$ \\ $$$$ \\ $$
Commented by aliesam last updated on 02/Jul/19
well done sir
$${well}\:{done}\:{sir} \\ $$
Commented by Prithwish sen last updated on 02/Jul/19
thank you
$$\mathrm{thank}\:\mathrm{you} \\ $$

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