28=10^x

解答

28 = 1 0^{x}

x = \frac{ln ( 28 )}{ln ( 10 )}

十进制

x = 1.44715 \dots

求解步骤

28 = 1 0^{x}

使用指数运算法则

ln (28) = x ln (10)

解

ln (28) = x ln (10) : x = \frac{ln ( 28 )}{ln ( 10 )}

x = \frac{ln ( 28 )}{ln ( 10 )}

4^{3 x - 1} = 8^{- 2 x + 1}

4 \cdot 5. 2^{x} = 3 \cdot 0.7 5^{x}

2^{x + 2} = 3^{x - 1}

3^{2 x + 2} - 3^{x + 2} = 4

so l v e f or x, t = e^{x + 2}