Add: 3x2−4x+1x2−16\dfrac{3}{x^2 - 4x} + \dfrac{1}{x^2 - 16}x2−4x3+x2−161.
3(x+4)+xx(x−4)(x+4)\dfrac{3(x+4) + x}{x(x-4)(x+4)}x(x−4)(x+4)3(x+4)+x
4x+12x(x−4)(x+4)\dfrac{4x + 12}{x(x-4)(x+4)}x(x−4)(x+4)4x+12
4x(x+4)\dfrac{4}{x(x+4)}x(x+4)4
3x+13x(x−4)(x+4)\dfrac{3x + 13}{x(x-4)(x+4)}x(x−4)(x+4)3x+13