6x2-[-3x2-(x-1)] 化简

6x2-[-3x2-(x-1)] 化简 x2+3x+9/x2-27+6x/9x-x2-x-1/6+2x 化简 化简x2+3x+9/x2-27+6x/9x-x2-x-1/6+2x 计算:x2-5x+6/x2-4x+3 + x2-4x+3/x2-2x+1 + x2-3x-4/1-x2 化简x(x2-3）+x2（x-3)-3x(x2-x-1) 7/x2+x+1/x2-x=6/x2-1 化简1/x2-3x+2 +1/x2-x +1/x2+x +1/x2+3x+2 解方程：1/x2+x +1/x2+3x+2 +1/x2+5x+6 +1/x2+7x+12 +1/x2+9x+20=5/x2+11x-708解方程：1/x2+x +1/x2+3x+2 +1/x2+5x+6 +1/x2+7x+12 +1/x2+9x+20=5/x2+11x-708 x2-3x-1=0,求①x2 1/x2;②x2-1/x2 x2-3x+1=0 x2/(x4-x2+1) x2-1/x2-5x+6 化简2x2-3/4（4x-6x2）+（x-3x2）求过程! 化简2x2-3/4（4x-6x2）+（x-3x2）求过程! 约分 1-x2/x2-3x-4 x2-4x+3分之x2-5x+6+s2-2x+1分之x2-4x+3+1-x2分之x2-3x-4的过程 1/(x2+x)+1/(x2+3x+2)+1/(x2+5x+6)+1/(x2+7x+12)=4/21x2是x的平方 (x-x2)(x2+x-6)分之(x2+3x)(x2-3x+2) 方括号代表根号（1）化简:[x2-6x+9]+[x2-8x+16](3