Question

[Đỗ Đào Vũ Long]

Tìm x, y biết: 2^x + 21^y = 505

Ai lm nhanh thì mik tick nhé!

Answer 1

[Xyz OLM]

Khi y \(\ge3\) => 2^x < 0 => x \(\in\varnothing\)

=> y < 3

=> y \(\in\left\{0;1;2\right\}\)

Khi y = 2 => 2^x = 64 => x = 7

Khi y = 1 => 2^x = 484 => x \(\in\varnothing\)

Khi y = 0 => 2^x =504 => x \(\in\varnothing\)

Vậy x = 7 ; y = 2

Answer 2

[✧ ( •̀ ω •́ )✧₸ĦV✧( •̀ ω •́ )✧]

\(Khi\text{ y}\ge3\Rightarrow2^x< 0\Rightarrow x\in\varnothing\)

\(\Rightarrow y< 3\)

\(\Rightarrow y\in\left\{0;1;2\right\}\)

\(Khi\text{ y}=2\Rightarrow2^x=64\Rightarrow x=7\)

\(Khi\text{ y}=1\Rightarrow2^x=484\Rightarrow x\in\varnothing\)

\(Khi\text{ y}y=0\Rightarrow2^x=504\Rightarrow x\in\varnothing\)

\(\text{Vậy x=7;y=2}\)

\(\text{Hok tốt!}\)

\(\text{@Kaito Kid}\)