为什么(6x^2-13x+6)(2x^2-5x+2)=(2x-3)(3x-2)(2x-1)(x-2)

*-----------------------------------------------*| 6 4 X | 8 X X | X X 5 || X X X | X X X | X 7 8 || X X X | X X X | X X X ||---------------+---------------+--------------- || X X X | X X X | 5 1 X || X X X | X 6 X | X X X || 8 X X | 3 5 X | 2 X X || x(x*x-6x-9)-x(x*x-8x-15)+2x(3-x) 填九宫格帮帮忙.x x 6 x x 7 x x 98 x x x 3 x 1 x x 9 x x 6 x 5 x 3 x x x 3 x x x x 1 8x x x 9 x 1 x x x2 1 x x x x 6 x x x 6 x 7 x 3 x x 1 x x 9 x 2 x x x 47 x x 8 x x 5 x x 为什么(6x^2-13x+6)(2x^2-5x+2)=(2x-3)(3x-2)(2x-1)(x-2) 解分式方程：1/X-2+1/X-6=1/X-7+1/X-11/X-2+1/X-6=1/X-7+1/X-11/(x-2)-1/(x-1)=1/(x-7)-1/(x-6)(x-1-x+2)/(x-2)(x-1)=(x-6-x+7)/(x-7)(x-6)1/(x-2)(x-1)=1/(x-7)(x-6)(x-2)(x-1)=(x-7)(x-6)x^2-3x+2=x^2-13x+4213x-3x=42-210x=40x=4 为什么要移向才能解 6：X=(5+X):2中的X为什么 x-x^2/6 x-x^2/6 因式分解(x-1)(x+2)(x+3)(x+6)-13 (x-1)(x+2)(x+3)(x+6)-13 约分：1、x*x-9/6-2x 2、x*x-1/x-x*x x/x-2+x-9/x-7=x+1/x-1+x-8/x-6, x/x-2+x-9/x-7=x+1/x-1+x-8/x-6, (x+3x+5x...+2009x)-(2x+4x+6x+...+2010x) x/x-3-5x/x^2-x-6计算 x^6-x^5+x^4-x^2+x-1 求一个数独答案X X X 9 X X X 8 2 X 6 3 X X 1 4 X 99 X 8 X X X X X XX X X 6 7 X 3 X XX 4 6 X 5 X 2 9 XX X 7 X 2 3 X X XX X X X X X 7 X 17 X 4 3 X X 6 2 X6 3 X X X 7 X X X 3(x^4)^6-2(x^5×x^3)^3+x^11×x^13+x^20×x^3×x