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A sequence of no. a1,a2,a3 ..... satisfi...

A sequence of no. `a_1,a_2,a_3 `..... satisfies the relation `a_n=a_(n-1)+a_(n-2)` for `nge2`. Find `a_4` if `a_1=a_2=1`.

Text Solution

Verified by Experts

Putting n=2 in the given relation
`a_3=a_1+a_2=2`
`therefore n=3 rArra_4=a_3+a_2=(2+1)=3`
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Knowledge Check

  • If a_1,a_2,.....a_n are in H.P., then the expression a_1a_2 + a_2a_3 + ... + a_(n-1)a_n is equal to

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    B
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    C
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    D
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