GATE 2023 MA – Question 27

Complex Analysis · Power Series and Singularities · 1 mark · Numerical answer

Near zero, $z/(1-z-z^2)=\sum_{n=0}^\infty a_nz^n$. Find a₆+a₅.

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Correct answer: 13 to 13

Explanation

Multiplying by 1−z−z² gives a₀=0,a₁=1 and a_n=a_(n−1)+a_(n−2). Thus a₂,…,a₆=1,2,3,5,8 and the requested sum is **13**.

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