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output formatting - How do I get a two-term polynomial with a leading negative sign to display in the correct (i.e. textbook) order?


The first three expressions evaluate as expected and the polynomial is displayed in what I would call "textbook" form. The last expression, however, switches the order of terms. Mathematica employs this change for two-term polynomials if it results in getting rid of the leading negative sign (at least that is the best I can deduce).


x^2 + x + 5 // TraditionalForm
(* x^2 + x + 5 *)

-x^2 + x + 5 // TraditionalForm
(* -x^2 + x + 5 *)


x^2 + x // TraditionalForm
(* x^2 + x *)

-x^2 + x // TraditionalForm
(* x - x^2 *)

These polynomials are the result of prior symbolic manipulation, so I cannot simply use HoldForm or the equivalent to maintain the desired order.


Is there a way to change this behavior in general so that the last expression displays as -x^2 + x? I can think of substitution rules to fix this particular example, but would like to find a robust solution that applies as transparently as possible across the board.


Edit



Additionally, PolynomialForm produces the same results:


PolynomialForm[-x^2 + x , TraditionalOrder -> True]
(* x - x^2 *)

PolynomialForm[-x^2 - x , TraditionalOrder -> True]
(* -x^2 - x *)

It seems that Mathematica will produce the traditional order for polynomial terms except when there are only two terms and reversing the order eliminates the leading negative sign.




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