So far, these are the functions/usable symbols: Addition, + Subtraction, - Division, / Multiplication, * Exponents, ^ Parentheses, () Square root, √(), option+v Absolute value, || (check below for details) sin, sin() cos, cos() tan, tan() Answer (The answer to your last equation), ans Pi, π, option+p on mac Do not put in any letters. If you need any help or do not understand anything, ask in the comments. Inputting these functions incorrectly will result in errors (as would a regular calculator but without an error message) For absolute value: When putting absolute value signs inside of absolute value signs, make sure to use parentheses to show that they are not two separate sets of absolute values. For example: |2+(|-3|)-1| NOT |2+|-3|-1| That would be interpreted as |2+| then -3 and then |-1|, two separate absolute values rather than |-3| being inside of the other absolute value signs. Yes I know that was hard to understand, absolute value signs are not my favorite either.