Question

Решите уравнения(дам 40 баллов)​

Answer 1

9.

$( \frac{1}{5} ) {}^{ |x - 4| } = 0.04 \\ ( \frac{1}{5} ) {}^{ |x - 4| } = \frac{1}{25} \\ ( \frac{1}{5} ) {}^{ |x - 4| } = ( \frac{1}{5} ) {}^{2} \\ |x - 4| = 2 \\ 1) \: x - 4 = 2 \\ x = 2 + 4 \\ x_{1} = 6 \\ 2) \: x - 4 = - 2 \\ x = - 2 + 4 \\ x_{2} = 2$

10.

$( \frac{2}{7} ) {}^{3x - 7} = 3.5 {}^{x} \\ ( \frac{2}{7} ) {}^{3x - 7} = ( \frac{7}{2} ) {}^{x} \\ ( \frac{2}{7} ) {}^{3x - 7} = ( \frac{2}{7} ) {}^{ - x} \\ 3x - 7 = - x \\ 3x + x = 7 \\ 4x = 7 \\ x = 7 \div 4 \\ x = 1.75$