Arithmetic series HELP PLEASE
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Answer:
5050
Step-by-step explanation:
∑_{n=1 to 50} (4n-1)
a1=4×1-1=3
a2=4×2-1=7
a3=4×3-1=11
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a50=4×50-1=199
n=50
Sn=n/2(a1+an)
S50=50/2(3+199)=50/2×202=50×101=5050