Scientific Calculator Tricks: Don't Blame the Tool

Your calculator is smarter than you think. But garbage in = garbage out. Here is how to stop making silly mistakes.

Trick 1: The PEMDAS Trap

Calculators follow the Order of Operations perfectly. Humans do not.
Input: 6 / 2(1+2)
Your Calculator sees: 6 / 2 * 3 → 3 * 3 → 9
Many students mistakenly think: 2(3) is grouped, so 6 / 6 = 1.
Fix: When in doubt, USE EXTRA PARENTHESES. 6 / (2*(1+2)).

Trick 2: Degrees vs. Radians (The Grade Killer)

In Calculus, almost everything is in Radians. In Physics or basic Geometry, you often use Degrees. Checking your mode should represent the first thing you do. If you are graphing y = sin(x) and it looks like a flat line, you are probably in Degree mode when you should be in Radian mode.

Trick 3: The 'Store' Function (STO)

Writing down intermediate numbers on paper and re-typing them leads to "Rounding Errors." If you round 1.666666 to 1.7 early in the problem, your final answer might be off by a lot. Use the STO (Store) button to save a variable to 'A' or 'X'. Then just recall 'A' later.

Trick 4: Negative (-) vs. Minus (-)

On many physical calculators (like TI-84), these are different buttons. The minus sign performs subtraction (5 - 3). The negative sign denotes a negative number (-5). Using the wrong one will give you a "Syntax Error".