Math police Memes

The eternal struggle of calculus students everywhere! First you write the integral of dx/x, then confidently declare it equals ln(x) + C. But wait—the math police have arrived with a photo of a disappointed mathematician! The absolute value bars around x are missing! The correct form is ln|x| + C, which accounts for negative values of x where the logarithm would otherwise be undefined. That tiny vertical line makes all the difference between mathematical glory and eternal shame.