Answers

2016-07-09T14:28:04+08:00
41 
an=3n+5
n=12
a12=3(12)+5
a12=41
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  • Brainly User
2016-07-09T18:12:54+08:00
First, find a₁:

a₁ = 3(1) + 5
a₁ = 3 + 5
a₁ = 8

Next, find the 12th term:
a₁₂ = 3(12) + 5
a₁₂ = 36 + 5
a₁₂ = 41

Now, find the sum of the first 12 terms:

S₁₂ = n/2 [a₁ + an]

S₁₂ = 12/2 [8 + 41)

S₁₂ = 6 (49)

S₁₂ = 294

ANSWER:  294
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