i was given the code: 
$A = -4;
$w = 500;
then

$re =
'/^\s*(\Q$A\E\s*\*?\s*\Qcos\E\s+\Q$w\E\s*\Qt\E\s+\QA\E||\Q$A\E\s*\*?\s
+*\Qcos\E\s*\(\s*\Q$w\E\s*\Qt\E\s*\)\s+\QA\E)\s*$/';

will accept answers in the following form:
-4cos 500t A
-4 cos 500t A
-4*cos 500t A
-4*cos(500t) A   -- and any number of spaces before and after *, t, ( 
+and )

[download]
It works great.. but that regular expression.. Jesus Christ.. Is there a way to dumb that down for me so that i can apply it to other situations, or would that take a complete O'Reilly book to figure out?

In reply to is there an easy way to dumb down this regular expression for me? by moltar512

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