Помогите с Алгеброй Срочно50 баллов

Решите задачу:

$\frac{1}{(x-2)(x-1)}+\frac{1}{x(x-1)}+\frac{1}{x(x+1)}+\frac{1}{(x+1)(x+2)}=\\=\frac{x(x+1)(x+2)+(x-2)(x+1)(x+2)+(x+2)(x-1)(x-2)+x(x-1)(x-2)}{x( x^{2}-1)(x^{2}-4)}= \\ =\frac{x((x+1)(x+2)+(x-1)(x-2))+( x^{2} -4)( x^{2} -1)}{x( x^{2}-1)(x^{2}-4)} = \\ = \frac{x( x^{2} +3x+2+ x^{2} -3x+2)+( x^{2} -4)( x^{2} -1)}{x( x^{2}-1)(x^{2}-4)}= \\ = \frac{x(2 x^{2} +4)+( x^{2} -4)( x^{2} -1)}{x( x^{2}-1)(x^{2}-4)} = \frac{2 x^{3}+4x+ x^{4 }-5 x^{2} +4 }{x( x^{2}-1)(x^{2}-4)} = \\$ $= \frac{ x^{4}+2 x^{3}-5 x^{2} +4x+4 }{x( x^{2}-1)(x^{2}-4)}$