$3\mathrm{.}7$ Explain why the following is not a description of a legitimate Turing

machine.

Mbad $=$

$$On input $$p$,$ a polynomial over variables x$1,...,$xk :

$1.$ Try all possible settings of x$1,...,$xk to integer values.

$2.$ Evaluate p on all of these settings.

$3.$ If any of these settings evaluates to $0,$ accept; otherwise, reject.$$