Graveyard

Non-algebraic terms (i.e math concepts that you might have not learned yet like trigonometric expressions: $sin(x)$; exponential expressions: $5^x$, and logarithms: $\log(x)$)

A term with a negative exponent after being simplified.

A term with a fractional exponent after being simplified.

A term with a negative exponent before being simplified.

A term with a fractional exponent before being simplified.