Conditional Equations Related to Drygas Functional Equations

Sadegh Izadi; Sedigheh Jahedi; Mehdi Dehghanian

doi:10.2478/amsil-2025-0015

Abstract

We determine the solutions of the conditional Drygas equation for functions f₁ and f₂ that satisfy (y² + y)f₁(x) = (x² + x)f₂(y) for all (x, y) ∈ ℝ² under the additional conditions y = x², or y = log(x), x > 0 or y = exp(x).

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Conditional Equations Related to Drygas Functional Equations

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