Question

c)x^3=8^2

d)x^20=x

e)2^x-15=17

Answer 1

Đề yêu cầu gì hả em?

Answer 2

Answer 3

a) \(x^3=8^2\)

\(\Rightarrow x^3=64\)

\(\Rightarrow x=4\)

Vậy: \(x=4\)

b) \(x^{20}=x\)

\(\Rightarrow x\left(x^{19}-1\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x=10\\x^{19}-1=0\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=0\\x=1\end{matrix}\right.\)

Vậy: \(x\in\left\{0;1\right\}\)

e) \(2^x-15=17\)

\(\Rightarrow2^x=32\)

\(\Rightarrow2^x=2^5\)

\(\Rightarrow x=5\)

Vậy: \(x=5\)