Why your calculator shows "Math ERROR"

"Math ERROR" never shows up at random. It's almost always one of these three causes.

The most common: division by zero, often hidden inside a fraction or a multi-step formula where the denominator becomes zero without you noticing.

Second cause: the square root of a negative number. If an intermediate step gives a negative number under a square root, your calculator refuses to continue — a good sign there's a sign error earlier in your work.

Third cause: a number too large for the display (overflow), often a sign that you multiplied instead of dividing somewhere.

The right reflex: don't just retype the calculation hoping it'll go through. Retrace your steps one by one to find where the problematic number showed up — that's where your error is, not in the calculator.