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1 year ago

Find the 13th term of the arithmetic sequence whose common difference is d=7 and whose first term is a1=-3

Mathematics

1 answer:

timama [110]1 year ago

3 0

Answer:

Step-by-step explanation:

the formula for an arithmetic sequence:

aₙ = a₁ + (n-1)d

where aₙ = the nth term

a₁ = the 1st term = -3

n = the term number = 13

d = the common difference = 7

Plugging in those values into the formula to find a₁₃:

a₁₃ = -3 + (13-1)7

= -3 + (12)7

= -3 + 84

= 81

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Step-by-step explanation:

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