Решаю уравнения, которые видны на изображении.
log2(6 - x) = 5
6 - x = 25
6 - x = 32
-x = 32 - 6
-x = 26
x = -26
Проверка:
log2(6 - (-26)) = log2(32) = log2(25) = 5
Ответ: x = -26
$${\frac{1}{4}}log_{ \frac{1}{4}}(12 - 4x) = -3$$
$$log_{ \frac{1}{4}}(12 - 4x) = -3 \cdot 4$$
$$log_{ \frac{1}{4}}(12 - 4x) = -12$$
$$12-4x=({1 \over 4})^{-12}$$
$$12-4x=4^{12}$$
$$4x=12-4^{12}$$
$$x={12-4^{12} \over 4}$$
$$x=3-4^{11}$$
$$x=3-4194304=-4194301$$
Ответ: $$x=-4194301$$
log5(7 - x) = log5(3 - x) + 1
log5(7 - x) - log5(3 - x) = 1
$$log_5(\frac{7-x}{3-x}) = 1$$
$$\frac{7-x}{3-x}=5$$
$$7-x=5(3-x)$$
$$7-x=15-5x$$
$$5x-x=15-7$$
$$4x=8$$
$$x=2$$
Проверка:
log5(7 - 2) = log5(3 - 2) + 1
log5(5) = log5(1) + 1
1 = 0 + 1
1 = 1
Ответ: x = 2
$$log_5(5 + 6x) = log_5(1 + 4x) + 1$$
$$log_5(5 + 6x) - log_5(1 + 4x) = 1$$
$$log_5(\frac{5+6x}{1+4x})=1$$
$$\frac{5+6x}{1+4x}=5$$
$$5+6x=5(1+4x)$$
$$5+6x=5+20x$$
$$20x-6x=5-5$$
$$14x=0$$
$$x=0$$
Проверка:
$$log_5(5 + 6 \cdot 0) = log_5(1 + 4 \cdot 0) + 1$$
$$log_5(5) = log_5(1) + 1$$
$$1=0+1$$
$$1=1$$
Ответ: x = 0
$$5^{log_{25}(2x-1)} = 3$$
$$5^{log_{5^2}(2x-1)} = 3$$
$$5^{{1 \over 2}log_{5}(2x-1)} = 3$$
$$(5^{log_{5}(2x-1)})^{1 \over 2} = 3$$
$$(2x-1)^{1 \over 2} = 3$$
$$2x-1 = 3^2$$
$$2x-1 = 9$$
$$2x = 10$$
$$x = 5$$
Проверка:
$$5^{log_{25}(2 \cdot 5-1)} = 3$$
$$5^{log_{25}(9)} = 3$$
$$5^{log_{5^2}(3^2)} = 3$$
$$5^{2log_{5^2}(3)} = 3$$
$$5^{2 \cdot {1 \over 2} log_{5}(3)} = 3$$
$$5^{log_{5}(3)} = 3$$
$$3 = 3$$
Ответ: x = 5