Answer:
-682
Step-by-step explanation:
[tex]S = 2 - 4 + 8 ... \\ \\ S= 2^1-2^2+2^3-2^4+2^5+...+2^9-2^{10}\\ \\ b_1 = 2, \quad q = -2,\quad n = 10 \\ \\ S = \dfrac{b_1\cdot (q^{10}-1)}{q-1} = \dfrac{2\cdot \Big[(-2)^{10}-1\Big]}{-2-1} = \dfrac{2^{11}-2}{-3} = \dfrac{2046}{-3} = -682[/tex]
