Rút gọn, rồi tính giá trị các phân thức sau : A=\(\dfrac{\left(2x^{2^{ }}+2x^{ }\right)\left(x-2\right)^2}{^{ }\left(x^{3^{ }}-4x\right)\left(x+1\right)}\)với x = \(\dfrac{1}{2}\)
B=\(\dfrac{x^3-x^{2^{ }}y+xy^2}{x^3+y^3}\)với x = -5 , y = 10
Rút gọn biểu thức:
\(\dfrac{x^2+xy}{x^2+xy+y^2}\) - [\(\dfrac{x\left(2x^2+xy-y^2\right)}{x^3-y^3}\) - 2 + \(\dfrac{y}{y-x}\)] : \(\dfrac{x-y}{x}\) - \(\dfrac{x}{x-y}\)
Rút gọn các biểu thức sau :
a)\(\dfrac{25xy^3\left(2x-y\right)^2}{75xy^2\left(y-2x\right)}\)
b)\(\dfrac{x^2-y^2}{x^2-y^2+xz-yz}\)
c)\(\dfrac{\left(2x+3\right)-x^2}{x^2-1}\)
d)\(\dfrac{3x^3-7x^2+5x-1}{2x^3-x^2-4x+3}\)
Rút gọn rồi tính giá trị biểu thức
\(\left[\left(\dfrac{x-y}{2y-x}-\dfrac{x^2+y^2+y-2}{x^2-xy-2y^2}\right):\dfrac{4x^4+4x^2y+y^2-4}{x^2+x+xy+y}\right]:\dfrac{x+1}{2x^2+y+2}\)
với x=-1,76 y=\(\dfrac{3}{25}\)
Rút gọn các phân thức sau:
a) \(\dfrac{x^6+2x^3y^3+y^6}{x^7-xy^6}\)
b) \(\dfrac{\left(2x^2+2x\right)\left(x-2\right)^2}{\left(x^3-4x\right)\left(x+1\right)}\)
c) \(\dfrac{x^3-x^2y+xy^2}{x^3+y^3}\)
d) \(\dfrac{a^2+b^2-c^2+2ab}{a^2-b^2+c^2+2ac}\)
e) \(\dfrac{2x^3-7x^2-12x+45}{3x^3-19x^2+33x-9}\)
R/gọn: \(\left(\dfrac{x^2}{x+y}+y\right).\left(\dfrac{1}{x^2-xy}-\dfrac{3y^2}{x^4-xy^3}-\dfrac{y}{x^3+x^2y+xy^2}\right)\)
1.Rút gọn :
a,\(\dfrac{xy^3-yx^3}{x^2-xy}\)
b,\(\dfrac{y\left(2x-x^2\right)}{x\left(2y+y^2\right)}\)
Rút gọn phân thức :
a) \(\dfrac{x^4-y^4}{y^3-x^3}\)
b) \(\dfrac{\left(2x-4\right)\left(x-3\right)}{\left(x-2\right)\left(3x^2-27\right)}\)
c) \(\dfrac{2x^3+x^2-2x-1}{x^3+2x^2-x-2}\)
Rút gọn các phân thức sau :
a) \(\dfrac{x^2-16
}{4x-x^2}\) ( x \(\ne\) x , x \(\ne\) 4 )
b) \(\dfrac{x^2+4x+3}{2x+6}\) ( x \(\ne\) -3 )
c) \(\dfrac{15x\left(x+y\right)^3}{5y\left(x+y\right)^2}\) ( y + ( x + y ) \(\ne\) 0 )
d) \(\dfrac{5\left(x-y\right)-3\left(y-x\right)}{10\left(x-y\right)}\) ( x \(\ne\) y )
e) \(\dfrac{2x+2y+5x+5y}{2x+2y-5x-5y}\) ( x \(\ne\) - y )
f)\(\dfrac{x^2-xy}{3xy-3y^2}\) ( x \(\ne\) y , y \(\ne\) 0 )
g) \(\dfrac{2ax^2-4ax+2a}{5b-5bx^2}\) ( b \(\ne\) 0 , x \(\ne\pm\)1 )
h) \(\dfrac{4x^2-4xy}{5x^3-5x^2y}\left(x\ne0,x\ne y\right)\)
i) \(\dfrac{\left(x+y\right)^2-z^2}{x+y+z}\left(x+y+z\ne0\right)\)
k)\(\dfrac{x^6+2x^3y^3+y^6}{x^7-xy^6}\left(x\ne0,x\ne y\right)\)
Help me!!!