My explanation as to why I didn't do so well grade-wise when I took Trigonometry & Advanced Calculus:
"Okay, trigonometry and calculus both deal with imaginary numbers.
Imaginary numbers, and they're represented by letters! No! Letters belong in language class, math is for numbers only. And what the hell is up with these imaginary numbers? If the math is so hard that they can't solve the equations without making up numbers, end of story -- problem unsolvable."