Obliczenie: PtyIbR - 1
S_n =
| (a_1a_n)* n |
| / 2 |
|
S_n =
$$S_{n}$$ = $$\frac{(a_{1a_n})\cdot n}{2}$$
| (a_1a_n)* n |
| / 2 |
S_n =
$$S_{n}$$ = $$\frac{a_{1a_n}\cdot n}{2}$$
| a_1a_n* n |
| / 2 |
S_n = 0.5* a_1a_n* n$$S_{n}$$ = $$0.5\cdot a_{1a_n}\cdot n$$