Question

2 задания с вариантами ответа

Answer 1

1) a₁ = - 5

a₂ = - 6

a₂ = a₁ + d

d = a₂ - a₁ = - 6 - (- 5) = - 6 + 5 =- 1

a₃ = a₂ + d = - 6 - 1 = - 7

a₄ = a₃ + d = - 7 - 1 = - 8

$S_{4}=\frac{a_{1}+a_{4}}{2}*4=(a_{1} +a_{4})*2=(-5-8)*2= -26$

2)

b₁ = - 8

b₂ = 16

b₂ = b₁ * q

q = b₂ : b₁ = 16 : (- 8) = - 2

b₃ = b₂ * q = 16 * (- 2) = - 32

b₃ = - 32