(x2+5x+4)2+2(x2+5x+4)2+1=(x2+.
(x2+5x+4)2+2(x2+5x+4)2+1=(x2+.
5x2—[x2+(4x—x2)—2(x2—3x)]
1/(x2+3x+2)+1/(x2+5x+6)+1/(x2+7x+12)=1/(x+4)
解分式方程:2/x2+5x+6 + 3/x2+x-6=4/x2-4
化简求值:3x2+(2x2-3x)-(-4x+5x2),其中x=2010.
因式分解 (x2-5x+4)(x2-x-2)-72
1/(x2+x)+1/(x2+3x+2)+1/(x2+5x+6)+1/(x2+7x+12)=4/21
解方程:1/x2+x +1/x2+3x+2 +1/x2+5x+6 +1/x2+7x+12 +1/x2+9x+20=5/x
先化简,再求值:(1)2x2-5x x2 4x,其中x=-3 (2)(3x2-xy-2y2)-2(x2 xy-2y2),
5x2+4-3x2-5x-2x2-5+6x.
(-2x2+3x)-[5x-(2x2+1)-x2].
解方程2/x2+x+3/x2-x=4/x2-1