Question

Реши уравнение методом введения новой переменной:

Answer 1

$\frac{lg^{2}x^{6}}{6}-lg1000x^{65}+53=0\\\\\frac{36lg^{2}x}{6}-(lg1000+lgx^{65})+53=0\\\\6lg^{2}x-(3lg10+65lgx)+53=0\\\\6lg^{2}x-3-65lgx+53=0\\\\6lg^{2}x-65lgx+50=0\\\\lgx=m,x>0$

$6m^{2}-65m+50=0\\\\D=(-65)^{2}-4*6*50=4225-1200=3025=55^{2}\\\\m_{1}=\frac{65-55}{12}=\frac{10}{12}=\frac{5}{6}\\\\m_{2}=\frac{65+55}{12}=\frac{120}{12}=10\\\\lgx=\frac{5}{6}\\\\x_{1}=10^{\frac{5}{6}}\\\\lgx=10\\\\x_{2}=10^{10} \\\\Otvet:\boxed{10^{\frac{5}{6}};10^{10}}$