check if an expression matches the quadratic formula

Parameters

 expr - any expression

Description

 • The IsQuadraticFormula command returns true when the input expr matches the quadratic formula.
 • The quadratic formula can be written in many subtly different ways, including use of &+- as opposed to ±, and use of different variable names.  This command helps to identify input steps that match a declared unevaluated quadratic formula with symbols for a, b, and c.
 • This command is used by Grading:-SolveFeedback to identify a step in a solution input that matches the quadratic formula.

Examples

 > $\mathrm{with}\left(\mathrm{Grading}\right):$
 > $\mathrm{IsQuadraticFormula}\left(\frac{\left(-'b'\right)±\left(\mathrm{sqrt}\left({'b'}^{2}-4'a''c'\right)\right)}{2'a'}\right)$
 ${\mathrm{true}}$ (1)
 > $\mathrm{IsQuadraticFormula}\left(\frac{\left(-'B'\right)±\left(\mathrm{sqrt}\left({'B'}^{2}-4'A''c'\right)\right)}{2'A'}\right)$
 ${\mathrm{true}}$ (2)

Compatibility