Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

If 
a_(1)=2,a_(2)=1 and 
a_(n)=2a_(n-1)+a_(n-2) then find the value of 
a_(5).
Answer:

If a1=2,a2=1 a_{1}=2, a_{2}=1 and an=2an1+an2 a_{n}=2 a_{n-1}+a_{n-2} then find the value of a5 a_{5} .\newlineAnswer:

Full solution

Q. If a1=2,a2=1 a_{1}=2, a_{2}=1 and an=2an1+an2 a_{n}=2 a_{n-1}+a_{n-2} then find the value of a5 a_{5} .\newlineAnswer:
  1. Understand the formula: Understand the recursive formula and initial conditions.\newlineThe recursive formula given is an=2an1+an2a_{n}=2a_{n-1}+a_{n-2}, which means each term is the sum of twice the previous term and the term before that. We are given a1=2a_{1}=2 and a2=1a_{2}=1.
  2. Find a3a_{3}: Find the value of a3a_{3} using the recursive formula.a3=2a2+a1a_{3} = 2a_{2} + a_{1}a3=2(1)+2a_{3} = 2(1) + 2a3=2+2a_{3} = 2 + 2a3=4a_{3} = 4
  3. Find a4a_{4}: Find the value of a4a_{4} using the recursive formula.a4=2a3+a2a_{4} = 2a_{3} + a_{2}a4=2(4)+1a_{4} = 2(4) + 1a4=8+1a_{4} = 8 + 1a4=9a_{4} = 9
  4. Find a5a_{5}: Find the value of a5a_{5} using the recursive formula.\newlinea5=2a4+a3a_{5} = 2a_{4} + a_{3}\newlinea5=2(9)+4a_{5} = 2(9) + 4\newlinea5=18+4a_{5} = 18 + 4\newlinea5=22a_{5} = 22

More problems from Write and solve direct variation equations