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These two equations are shown in the system:The system is linear in A1, A2, A3, and A4 .
Not linear. That shows an exponent of 2 on the w. If I misunderstand, then w is not a variable; but A1, A2, and A3 must be the variables. If this latter is the case, then yes; linear system.dA1 + cA2 + w^2 A3 = 1
dA2 + w^2A4 = 0