public override TermBase Raise(TermBase power) => power switch {
public override TermBase Div(TermBase b) => b switch {
public override TermBase Div(TermBase b) => b is TermZero _ ? throw new DivideByZeroException($"{this}/{b}") : new TermZero();
public override bool Equals(TermBase other) => other is TermZero;
public override TermBase Mult(TermBase b) => new TermZero();