#958 · Algebra · Linear equations

Continued proportion identity II

If $a, b, c, d$ are in continued proportion, prove that $2 a + 3 d : 3 a - 4 d = 2 a^{3} + 3 b^{3} : 3 a^{3} - 4 b^{3}$ .

~12 minProof · checked by AIcontinued proportionratios

H. S. Hall & S. R. Knight, Higher Algebra (1891) · Ch. II. Proportion, Examples II, No. 9

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