若−12≤x≤1,则式子x2−2x+1+x2−6x+9+4x2+4x+1等于( )
若−12≤x≤1,则式子x2−2x+1+x2−6x+9+4x2+4x+1等于( )
计算:(1)x2+9xx2+3x+x2−9x2+6x+9
若x2-x-2=0,则x2−x+23(x2−x)2−1+3的值等于( )
若-2x2+5x-2>0,则4x2−4x+1+2|x−2|等于( )
(x2+3x+9)/(x2-27)+(6x)/(9x-x2)-(x-1)/(6+2x)
(1)12x+6+13−x+x2(x2−9);
化简:根号(x2+6x+9)+根号(x2-2x+1)-根号(x2-4x+4)
解方程:1/x2+x +1/x2+3x+2 +1/x2+5x+6 +1/x2+7x+12 +1/x2+9x+20=5/x
若根式根号(x2-6x+9)+根号(x2-4x+4)+根号(x2-10x+25)+根号(x2+2x+1)的值为常数,则实
要使代数式x2−2x−3x2−1的值等于0,则x等于( )
1/(x2+3x+2)+1/(x2+5x+6)+1/(x2+7x+12)=1/(x+4)
式子√x2+2x+工,√-x2-4x-5,√18,√-1-x2中,有意义的