2*log_{2}(3x-7)=10

解答

2 \cdot lo g_{2} (3 x - 7) = 10

x = 13

求解步骤

2 lo g_{2} (3 x - 7) = 10

两边除以

2

lo g_{2} (3 x - 7) = 5

使用对数运算法则

3 x - 7 = 32

解

3 x - 7 = 32 : x = 13

x = 13

验证解:

x = 13

真

解是

x = 13

4 ln (x^{2}) - 7 ln (x) + ln (x + 3) = 0

6 ln (x) - 3 = 2 - ln (x)

lo g_{8} (28 k - 20) + 15 = 18

2 ln (x) = ln (2) + ln (x + 4)

\frac{- 2 ln ( x ) + 1}{x ^{3}} = 0