316-ա.

ա)

x₁ = 2
x₂ = 4
x₃ = 6
x₄ = 8
x₅ = 10
x₆ = 12

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317-ա,գ.

ա)

x_n = n

գ)

x_n = 4n

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318-ա.

ա)

a_n = 3n – 1
a₁ = 3 – 1 = 2
a₂ = 3 * 2 – 1 = 6 – 1 = 5
a₅ = 3 * 5 – 1 = 15 – 1 = 14
a₁₀₀ = 3 * 100 – 1 = 300 – 1 = 299

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321-ա,գ.

ա)

a_n = 3n + 2
a₁ = 3 + 2
a₂ = 3 * 2 + 2 = 6 + 2 = 8
a₃ = 3 * 3 + 2 = 9 + 2 = 11
a₁₀ = 3 * 10 + 2 = 30 + 2 = 32

գ)

cⁿ = (-2)ⁿ
c¹ = (-2)¹ = -2
c² = (-2)² = 4
c³ = (-2)³ = -8
c¹⁰ = (-2)¹⁰ = 1024

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323-ա,գ.

ա)

a₁ = 2, a_{n + 1} = a_n + 3
a₂ = a₁ + 3 = 2 + 3 = 5
a₃ = a₂ + 3 = 5 + 3 = 8
a₄ = a₃ + 3 = 8 + 3 = 11
a₅ = a₄ + 3 = 11 + 3 = 14

գ)

c₁ = 4, c_{n + 1} = c_n – 8
c₂ = c₁ – 8 = 4 – 8 = -4
c₃ = c₂ – 8 = -4 – 8 = -12
c₄ = c₃ – 8 = -12 – 8 = -20
c₅ = c₄ – 8 = -20 – 8 = -28

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ՏՆԱՅԻՆ․

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316-բ.

բ)

x_n = 2n
x₇ = 2 * 7 = 14
x₈ = 2 * 8 = 16
x₂₀ = 2 * 20 = 40

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317-բ,դ.

բ)

x_n = 2n – 1

դ)

x_n = 1/n

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318-բ.

բ)

a_n = 3 + 2(n – 1)
a₁ = 3 + 2 * 0 = 3
a₂ = 3 + 2 * 1 = 5
a₁₂ = 3 + 2 * 11 = 3 + 22 = 25
a₃₀ = 3 + 2 * 29 = 3 + 58 = 61

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321-բ.

բ)

b_n = 16 * (½)n
b₁ = 16 * ½ = 8
b₂ = 16 * ¼ = 4
b₃ = 16 * ¹/₈ = 2
b₁₀ = 16 * ¹/₁₀₂₄ = ¹/₆₄

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323-բ,դ.

բ)

b₁ = -2, b_{n + 1} = 5 * b_n
b₂ = 5 * b₁ = 5 * -2 = -10
b₃ = 5 * b₂ = 5 * -10 = -50
b₄ = 5 * b₃ = 5 * -50 = -250
b₅ = 5 * b₄ = 5 * -250 = -1250

դ)

x₁ = 8, x_{n + 1} = 0,25 * x_n
x₂ = 0,25 * x₁ = 0,25 * 8 = 2
x₃ = 0,25 * x₂ = 0,25 * 2 = ¹/₂
x₄ = 0,25 * x₃ = 0,25 * ¹/₂ = ¹/₈
x₅ = 0,25 * x₄ = 0,25 * ¹/₈ = ¹/₃₂