\(=\dfrac{x^2+6x+9-x^2+6x-9+x^2-9x}{\left(x-3\right)\left(x+3\right)}=\dfrac{x^2+3x}{\left(x-3\right)\left(x+3\right)}=\dfrac{x\left(x+3\right)}{\left(x-3\right)\left(x+3\right)}=\dfrac{x}{x-3}\)
Bài 2: Tìm x biết:
1,x\(^2\)+4x+4=25
2,(5-2x)\(^2\)-16=0
3,(x-3)\(^3\)-(x-3)(x\(^2\)+3x+9)+9(x+1)\(^2\)=15
4,3(x+2)\(^2\)+(2x-1)\(^2\)-7(x-3)9x+3)=36
5,(x-3)(x\(^2\)+3x+9)+x(x+2)(2-x)=1
6,(2x+1)\(^2\)-4(x+2)\(^2\)=9
7,(x+3)\(^{^{ }2}\)-(x-4)(x+8)=1
phân tích thành nhân tử
\(4x^3 -4x^2 -9x+9\)
\(x^3 +6x^2 +11x+6\)
\(x^2 y-x^3 -9y+9x\)
\(a)(\frac{9}{x^3-9x}+\frac{1}{x+3}):(\frac{x-3}{x^2+3x}-\frac{x}{3x+9}) b)\frac{x+1}{x+2}(\frac{x+2}{x+3}:\frac{x+3}{x+1}) c)\frac{8}{(x^2+3)(x^2+3)}+\frac{2}{x^2+3}+\frac{1}{x+1}\)
a, [(x/x^2-25) - (x-5/X^2+5x)] : (2x-5/x^2+5x) + ( x/ 5-x)
b, [(9/x^3-9x) + (1/x+3)] : [(x-3/x^2+ 3x) - ( x/3x+9)]
c, (1/x-1) - (x^3-x/x^2+1) . [(x/x^2+1-2x) + (1/1-x^2)]
Rút gọn biểu thức :
a/ (x-3)(\(x^2\)+3x+9)-(\(x^2\)-1)(9x+27)
b/ (x-2)(\(x^2\)+2x+4)-x(x-3)(x+3)
2. Tìm x: ( x - 2 ) 3 - ( x + 1 ) 3 + 9x ( x + 1 ) - 9 = 0
1. Rút Gọn
a) -5x (x-3).(2x+4)-(x+3)(x-3)+(5x-2)(3x+4)
b) (4x-1)x(3x+1)-5x^2x(x-3)-(x-4)x(x-5)-7(x^3-2x^2+x-1)
c) (5x-7)(x-9)-(3-x)(2-5x)-2x(x-4)
d)(5x-4)(x+5)-(x+1)(x^2-6)-5x+19
e)(9x^2-5)(x-3)-3x^2(3x+9)-(x-5)(x+4)-9x^3
g) (x-1)^2 - (x+2)^2
Thanks mn nhiều ạ
\(\left(\frac{X^2+3X}{X^3+3X^2+9X+27}+\frac{3}{X+9}\right):\left(\frac{1}{X-3}-\frac{6X}{X^3-3X^2+9X-27}\right)\)
A=(9/x^3-9x+1/x+3) : (x-3/x^2+3x-x/3x+9)
a.Tính A khi x^2-5x=6
b.Tìm x để A=2
c.Tìm x thuộc Z để A thuộc Z
