SolveAlways

SolveAlways[eqns, vars] gives the values of parameters that make the equations eqns valid for all values of the variables vars.

Examples

Find parameters that make an equation always true:

SolveAlways[a x^2 + b x + c == (x - 1)(x - 2), x]
(* {{a -> 1, b -> -3, c -> 2}} *)

Solve for coefficients of a polynomial identity:

SolveAlways[a + b x + c x^2 == 3 + 2 x - x^2, x]
(* {{a -> 3, b -> 2, c -> -1}} *)

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