Відповіді на вправи: 577

1) x_n = 2n;

x₁ = 2 • 1 = 2;

x₂ = 2 • 2 = 4;

x₃ = 2 • 3 = 6;

x₄ = 2 • 4 = 8;

x₅ = 2 • 5 = 10;

(x_n) = 2; 4; 6; 8; 10.

2) x_n = 3n – 1;

x₁ = 3 • 1 – 1 = 2;

x₂ = 3 • 2 – 1 = 5;

x₃ = 3 • 3 – 1 = 8;

x₄ = 3 • 4 – 1 = 11;

x₅ = 3 • 5 – 1 = 14;

(x_n) = 2; 5; 8; 11; 14.

3) x_n = $\frac{n+1}{5}$;

x₁ = $\frac{1+1}{5}$ = $\frac{2}{5}$;

x₂ = $\frac{2+1}{5}$ = $\frac{3}{5}$;

x₃ = $\frac{3+1}{5}$ = $\frac{4}{5}$;

x₄ = $\frac{4+1}{5}$ = $\frac{5}{5}$ = 1;

x₅ = $\frac{5+1}{5}$ = $\frac{6}{5}$ = 1$\frac{1}{5}$;

(x_n) = $\frac{2}{5}$; $\frac{3}{5}$; $\frac{4}{5}$; 1; 1$\frac{1}{5}$.

4) x_n = n² + 1;

x₁ = 1² + 1 = 2;

x₂ = 2² + 1 = 5;

x₃ = 3² + 1 = 10;

x₄ = 4² + 1 = 17;

x₅ = 5² + 1 = 26;

(x_n) = 2; 5; 10; 17; 26.