1. \(x^{100}=x\)
\(TH1:x=0\)
Khi đó \(0^{100}=0\)
\(TH1:x\) ≠ \(0\)
Khi đó \(x^{100}=x\)
⇒\(x^{100}:x=1\)
⇒ \(x^{99}=1\)
⇒\(x=1\)
Vậy \(x\) ∈ \(\left\{0;1\right\}\)
1. x100=x
x100-x=0
x(x99-1)=0
=> x=0 hoặc x99-1=0
x99=1
x=1
Vậy x={0;1}
3. 10x:5y=20y
10x=20y.5y
10x=100y
10x=102y
=> x=2y
=>10x:5y=20ythỏa mãn khi x=2y
https://hoc24.vn/hoi-dap/question/665304.html
1.x100=x
TH1: x=0
Khi đó 0100=0
TH2: x ≠ 0
Khi đó:
x100=x
⇒x100: x = 1
⇒ x99 = 1⇒x =1
Vậy x ∈ {0;1}