Finding the derivative of a polynomial.
Take any polynomial, eg/ y=x3+1/2x2-3x+9. Then dy/dx=3x,+x-3, in this case. This is because, when deriving in this sense, you take each term in x, multiply it by its index, and reduce that index by 1.
In a general sense, for y=(n0)xn+(n1)xn-1+...+(nn-1)xn-(n-1)+(nn), dy/dx=(n)(n0)xn-1+(n-1)(n1)xn-2+...+(n-(n-1))(nn-1). Multiply the x term by the power, reduce the power by one. This works for all powers, even non-integers.
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