Obliczenia :
[tex]a_1=2, \ a_2=4, \ a_3=8\\\\q=\frac{a_2}{a_1}=\frac{4}{2}=2\\\\S_n=a_1\cdot\frac{1-q^n}{1-q}\\\\S_{10}=2\cdot\frac{1-2^{10}}{1-2}=2\cdot\frac{1-1024}{-1}=2\cdot\frac{-1023}{-1}=2\cdot1023=\boxed{2046}[/tex]
Odpowiedź:
a₁ = 2
a₂ = a₁q = 4
a₃ = a₁q² = 8
q - iloraz ciągu = a₃/a₂ = a₂/a₁
q = 8/4 = 4/2 = 2
S₁₀ = a₁(1 - q¹⁰)/(1 - q) = 2(1 - 2¹⁰)/(1 - 2) = 2(1 - 1024)/(- 1) = 2 * (- 1023)/(- 1) =
= - 2046/(- 1) = 2046
