If {a₁} = {a₂} = 2,{aₙ} = {a_{n - 1}} - 1(n > 2) , then {a₅} is

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8. Sequences and Series

easy

If ${a_1} = {a_2} = 2,\;{a_n} = {a_{n - 1}} - 1\;(n > 2)$, then ${a_5}$ is

A

$1$

B

$- 1$

C

$0$

D

$- 2$

Solution

(b) Obviously, ${a_3} = {a_2} – 1 = 2 – 1 = 1$

${a_4} = {a_3} – 1 = 1 – 1 = 0$

${a_5} = {a_4} – 1 = 0 – 1 = – 1.$

Standard 11

Mathematics

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