Question

Tìm số TN x biết x\(^{18}\) - x\(^3\) = 0 

Answer 1

\(x^{18}-x^3=0\)

\(\Rightarrow x^3.\left(x^{15}-1\right)=0\)

\(\Rightarrow x^3=0\) hoặc \(x^{15}-1=0\)

+) \(x^3=0\Rightarrow x=0\)

+) \(x^{15}-1=0\)

\(\Rightarrow x^{15}=1\)

\(\Rightarrow x=1\)

Vậy \(x\in\left\{0;1\right\}\)

Answer 2

so cac so tu nhien co hai chu so la