#959 · Algebra · Linear equations

Continued proportion identity III

If $a, b, c, d$ are in continued proportion, prove that $(a^{2} + b^{2} + c^{2}) (b^{2} + c^{2} + d^{2}) = (ab + b c + c d)^{2}$ .

~12 minProof · checked by AIcontinued proportionalgebraic identity

H. S. Hall & S. R. Knight, Higher Algebra (1891) · Ch. II. Proportion, Examples II, No. 10

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