x-1-x+2分之8乘x+3分之x+1

（1）x²分之x²+x乘x²-1分之x=(x²+x)/x²*x/(x²-1)=x(x+1)/x²*x/[(x+1)(x-1)]=1

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1乘2分之X+2乘3分之X+...+2010乘2011分之X=2010==>x(1-1/2)+x*(1/2-1/3)+...+x(1/2010-1/2011)=2010==>x(1-1/2+1/2+1

1乘2分之X+2乘3分之X+.+2003乘2004分之X=2003x-x/2+x/2-x/3+.+x/2003-x/2004=2003x-x/2004=20032003x/2004=2003x=200

原式=(x+1)(x-1)/x*x/(x+1)+3x+1=x-1+3x+1=4x

原式=[(1-1分之x+5)-(1-1分之x+4))+(1-1分之x+3)-(1-1分之x+2)]*[(x+3)(x+5)]\(x^2+7x+13)=[(1分之x+2)-(1分之x+3)+(1分之x+

1乘于2分之X+2乘于3分之X+3乘于4分之X+4乘于5分之X+5乘于6分之X+6乘于7分之X+.+2005乘于2006分之X=2005x(1-1/2+1/2-1/3+1/3-1/4+······+1

1、(x-3分之2x-x+3分之x)乘x分之x平方-9=［2X(X+3)-X(X-3)］/［(X-3)(X+3)］*(X+3)(X-3)/X=［2X^2+6X-X^2+3X］/X=X+9当X=1时,原

1/(1*2)=1-1/2,1/(2*3)=1/2-1/3,.1/(98*99)=1/98-1/99,1/(99*100)=1/99-1/100,1/(1*2)+1/(2*3)+.+1/(99*100

[(x-2)分之3x-(x+2)分之x]乘x分之(x²-4)=[(x-2)分之3x]乘x分之(x²-4)-[(x+2)分之x]乘x分之(x²-4)=3(x+2)-(x-2

1乘2分之x+2乘3分之x+3乘4分之x+.+2009乘2010分之x=X(1/(1*2)+1/(2*3)+...+1/(2009*2010))=X*((1-1/2)+(1/2-1/3)+.+(1/2

=[(x+2)/x(x-2)-(x-1)/(x-2)²]×x/(4-x)=[(x²-4-x²+4)/x(x-2)²]×x/(4-x)=1/(x-2)²

[3x/(x-1)-x/(x+1)]×(x²-1)/x=x[3(x+1)-(x-1)]/(x²-1)×(x²-1)/x=2x+4当x=√2-2时,原式=2x+4=2√2

原式=1/(x+1)*[(x-3)/(x+3)^2+2/(x+3)]-x/(x+3)(x-3)=1/(x+1)[3(x+1)/(x+3)^2]-x/(x+3)(x-3)=3/(x+3)^2-x/(x+

x/1×2+x/2×3+...+x/2887×2008=2005x(1-1/2+1/2-1/3+...+1/2006-1/2007+1/2007-1/2008)=20052007x/2008=2005

提出X=X(1-1/2+1/2-1/3+...+1/2005-1/2006)=X*2005/2006

左边进行转化得：[1-(1/2)+(1/2)-(1/3)+(1/4)-(1/5)……+(1/2003)-(1/2004)]x=2003[1-(1/2004)]x=2003(2003/2004)x=20

（1）（x²-9分之x+3+6+x-x²分之x)乘4x-6分之3-x=[(x+3)/(x+3)(x-3)-x/(x+2)(x-3)]×(3-x)/2(2x-3)=[(x+2-x)/

1乘2分之x+2乘3分之x+3乘4分之x+.+2009乘2010分之x=X(1/(1*2)+1/(2*3)+...+1/(2009*2010))=X*((1-1/2)+(1/2-1/3)+.+(1/2

X/(1×2)+X/(2×3)+X/(3×4)+.+X/(2003×2004)=2003X×{1/(1×2)+1/(2×3)+1/(3×4)+.+1/(2003×2004)}=2003X×{1-1/2