#1642 · Algebra · Sequences & series

Annuity Purchase Relations

If $a, b, c$ years' purchase must be paid for an annuity to continue $n, 2 n, 3 n$ years respectively; show that $a^{2} - ab + b^{2} = a c$ .

~20 minProof · checked by AIannuitiesgeometric series

H. S. Hall & S. R. Knight, Higher Algebra (1891) · Ch. XVIII. Interest and Annuities, Examples XVIII.b, No. 14

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