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32 votes
32 votes
If a1 = 7 and an = an-1 + 4 then find the value of a4.

User Mohamed Khamis
by
3.0k points

2 Answers

19 votes
19 votes

Put values get answer

  • a_n=a_(n-1)+4
  • a_4=a_3+4
  • a_4=a_2+4+4
  • a_4=a_1+4+4+4
  • a_4=7+12
  • a_4=19
User Magnus Melwin
by
3.2k points
10 votes
10 votes

Answer:


a_4=19

Explanation:

Given:


  • a_1=7

  • a_n=a_(n-1)+4


\implies a_2=a_(1)+4=7+4=11


\implies a_3=a_(2)+4=11+4=15


\implies a_4=a_(3)+4=15+4=19

User MDMower
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3.2k points