Арифметикалық және геометриялық прогрессия

$$d=a_{n+1}-a_n$$

$$d=a_n-a_{n+1}$$

$$q=\frac{b_{n+1}}{b_n}$$

$$q=\frac{b_n}{b_{n+1}}$$

$$d=a_{n+1}-a_n$$

$$d=a_n-a_{n+1}$$

$$q=\frac{b_{n+1}}{b_n}$$

$$q=\frac{b_n}{b_{n+1}}$$

$$a_n=a_1+\left(n-1\right)d$$

$$a_n=a_1+\left(n+1\right)d$$

$$b_n=b_1q^{n-1}$$

$$b_n=b_1q^{n+1}$$

$$a_n=a_1+\left(n-1\right)d$$

$$a_n=a_1+\left(n+1\right)d$$

$$b_n=b_1q^{n-1}$$

$$b_n=b_1q^{n+1}$$

$$S_n=\frac{2a_1+\left(n-1\right)d}{2}\cdot n$$

$$S_n=\frac{a_1+a_n}{2}\cdot n$$

$$S_n=\frac{2a_1+\left(n+1\right)}{2}\cdot n$$

$$S_n=\frac{b_1\left(q^n-1\right)}{q-1}$$

$$S_n=\frac{2a_1+\left(n-1\right)d}{2}\cdot n$$

$$S_n=\frac{a_1+a_n}{2}\cdot n$$

$$S_n=\frac{b_1q^{n-1}}{q-1}$$

$$S_n=\frac{b_1\left(q^n-1\right)}{q-1}$$

$$S_n=\frac{2a_1+\left(n-1\right)d}{2}\cdot n$$

$$S_n=\frac{a_1+a_n}{2}\cdot n$$

$$S_n=\frac{b_1q^{n-1}}{q-1}$$

$$S_n=\frac{b_1}{1-q}$$