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33 votes
33 votes
Find a1 for a geometric Sequence
if r=5 and a6=1000

User Findall
by
3.1k points

1 Answer

9 votes
9 votes

Answer:

  • The first term is 0.32

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Given

  • GP with r = 5, a₆ = 1000

Use the nth term equation:

  • aₙ = a₁*rⁿ⁻¹

Substitute and solve for a₁:

  • 1000 = a₁*5⁵
  • 1000 = a₁*3125
  • a₁ = 1000/3125
  • a₁ = 0.32
User Matzahboy
by
3.2k points