1/(x+1)(x+2)+1/(x+2)(x+3)+1/(x+3)(x+4)+……+1/(x+1997)(x+1998)

x+2/x+1-x+3/x+2-x+4/x+3+x+5/x+4 x^5+x^4 = (x^3-x)(x^2+x+1)+x^2+x |X-1|+|X-2|+|X-3|+|X-4|+|X-5|+|X-6|+|X-7|+|X-8|+|X-9|+|X-10| 1x+2x+3x+4x+5x+6x+7x…+99x=100 x-1)(X-2)(x-3)...(x-50)+x(x-2)(X-3)...(X-50)+...+x(x-1)(x-2) x(2-1/x)+x/(x^2-2x)÷(3-x)/(x^2-4) 1+x+x^2+x^3+.+x^99+x^100 已知x^2+x=-1 你能求x^2013+x^2012+x^2011+x^2010+x^2009+…+x^4+x^3+x x^4+x^3+x^2+x+1=0,x^2006+x^2005+x^2004+x^2003+x^2002 1X+2X+3X…+98X+99X+100X=50500X X等于多少? |x^2-3x-4|>x+1 (x+1-1/1-x)÷(x-x²/x-1) (x-4/x-x-6+ x+2/x-3)÷x+1/x-3