Question

Решить неравенство: (2/7)^(3(x-(1/3)))<(4/49)^x²

Answer 1

$(\frac{2}{7})^{3(x-\frac{1}{3})}\ \textless \ (\frac{4}{49})^{x^2}\\(\frac{2}{7})^{3x-1}\ \textless \ (\frac{2}{7})^{2x^2}\\3x-1\ \textgreater \ 2x^2\\2x^2-3x+1\ \textless \ 0\\D=9-8=1\\x_{1,2}=\frac{-bб\sqrt{D}}{2a}=\frac{3б1}{4}\to\left[\begin{array}{ccc}x_1=\frac{3+1}{4}=1\\x_2=\frac{3-1}{4}=\frac{1}{2}\end{array}\right\\\boxed{\frac{1}{2}\ \textless \ x\ \textless \ 1}$

ответ: x∈(0,5; 1)