Question

Simple questions points!!! :) Will also give you brainliest Answer questions 3-6

Answer 1

Answer:

3. aₙ = -9n +7

4. d = -2.4

5. a₆ = 45

6. aₙ = 133 + 4n

Step-by-step explanation:

Question 3.

a₁ = -2; aₙ = aₙ₋₁ - 9

The explicit rule for an arithmetic sequence is

        aₙ = a₁ + d(n -1 )

         d = aₙ - aₙ₋₁

        aₙ = aₙ₋₁ - 9     Subtract aₙ₋₁ from each side

aₙ - aₙ₋₁ = -9

         d = -9

For this sequence,  

aₙ = -2 – 9(n - 1)     Remove parentheses

aₙ = -2 - 9n + 9      Combine like terms

aₙ = -9n + 7

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Question 4

d = aₙ - aₙ₋₁

a₂ - a₁ = 6.2 – 8.6 = -2.4

a₃ - a₂ = 3.8 – 6.2 = -2.4, etc.

The common difference is

d = -2.4

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Question 5

aₙ = 8n – 3     Substitute the value of n

a₆ = 8×6 – 3

a₆ = 48 - 3

a₆ = 45

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Question 6

a₁ = 137; d = 4

aₙ = a₁ + d(n -1 )

aₙ = 137 + 4(n -1 )

aₙ = 137 + 4n -4

aₙ = 133 + 4n