几道初中数学题..要有过程 注:x^2 表示x的2次方1.化简:(9x^2+3x)/(x^2+6x+9) * (x^3+27)/(x^2-3x) ÷ (x^2-3x+9)/(x^2-9)2.化简x - x÷{(x^2-y^2)/(x^3+y^3) * [(x-(x^2+y^2)/y ) ÷ (1/x - 1/y)3.化简分式: (x^3 + 5x^2 + 3x - 9)/(x^3
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几道初中数学题..要有过程 注:x^2 表示x的2次方1.化简:(9x^2+3x)/(x^2+6x+9) * (x^3+27)/(x^2-3x) ÷ (x^2-3x+9)/(x^2-9)2.化简x - x÷{(x^2-y^2)/(x^3+y^3) * [(x-(x^2+y^2)/y ) ÷ (1/x - 1/y)3.化简分式: (x^3 + 5x^2 + 3x - 9)/(x^3
几道初中数学题..要有过程 注:x^2 表示x的2次方
1.化简:(9x^2+3x)/(x^2+6x+9) * (x^3+27)/(x^2-3x) ÷ (x^2-3x+9)/(x^2-9)
2.化简x - x÷{(x^2-y^2)/(x^3+y^3) * [(x-(x^2+y^2)/y ) ÷ (1/x - 1/y)
3.化简分式: (x^3 + 5x^2 + 3x - 9)/(x^3 + 6x^2 + 5x - 12)
4.若 (x^2 +1)/x =3 ,则 (x^3 + 1/x^3 +32)/(x^4 + 1/x^4 + 3)=?
几道初中数学题..要有过程 注:x^2 表示x的2次方1.化简:(9x^2+3x)/(x^2+6x+9) * (x^3+27)/(x^2-3x) ÷ (x^2-3x+9)/(x^2-9)2.化简x - x÷{(x^2-y^2)/(x^3+y^3) * [(x-(x^2+y^2)/y ) ÷ (1/x - 1/y)3.化简分式: (x^3 + 5x^2 + 3x - 9)/(x^3
1
(9x^2+3x)/(x+3)^2* (x^2-3x+9)(x+3)/x(x-3)*(x^2-9)/(x^2-3x+9)
=3x
2
3
=(x-1)(x+3)^2/(x-1)(x+3)(x-4)
=x+3/(x-4)
4
(x^2 +1)/x =3
x+1/x=3
liang bian ping fang
x^2+1/x^2=9-2=7
liang bian ping fang
x^4+1/x^4=49-2=47
x^3 + 1/x^3=(x^2+1/x^2-1)(x+1/x)=18
gu yuan shi=50/50=1