a)(x-1)(x+1)(x+2)
=(x2-1)(x+2)
=x3-x+2x2-2
b)\(\dfrac{1}{2}\)x2y(2x+y)(2x-y)
=\(\dfrac{1}{2}\)x2y(4x2-y2)
=2x4y-\(\dfrac{1}{2}\)x2y3
c)(x-\(\dfrac{1}{2}\))(x+\(\dfrac{1}{2}\))(4x-1)
=(x2-\(\dfrac{1}{4}\))(4x-1)
=4x3-x2-x+\(\dfrac{1}{4}\)
Thực hiện các phép tính sau:
a).\(\left(\dfrac{2x+1}{2x-1}-\dfrac{2x-1}{2x+1}\right):\dfrac{4x}{10x-5}\)
b). \(\left(\dfrac{1}{x^2+1}-\dfrac{2-x}{x+1}\right):\left(\dfrac{1}{x}+x-2\right)\)
c). \(\dfrac{1}{x-1}-\dfrac{x^3-x}{x^2+1}.\left(\dfrac{1}{x^2-2x+1}+\dfrac{1}{1-x^2}\right)\)
d). \(\left(\dfrac{x^2+xy}{x^3+x^2y+xy^2+y^3}+\dfrac{y}{x^2+y^2}\right):\left(\dfrac{1}{x-y}-\dfrac{2xy}{x^3-x^2y+xy^2-y^3}\right)\)
Thực hiện phép tính :
a) (x-1)(x+1)(x+2)
b) \(\dfrac{1}{2}x^2y^2\left(2x+y\right)\left(2x-y\right)\)
c)\(\left(x-\dfrac{1}{2}\right)\left(x+\dfrac{1}{2}\right)\left(4x-1\right)\)
Thực hiện phép tính :
a) \(\left(5x-2y\right)\left(x^2-xy+1\right)\)
b) \(\left(x-1\right)\left(x+1\right)\left(x+2\right)\)
c) \(\dfrac{1}{2}x^2y^2\left(2x+y\right)\left(2x-y\right)\)
bài 1 ;thực hiện phép tính
a,(x-1).(x+1).(x+2)
b,\(\dfrac{1}{2}x^2y^2\).(2x+y).(2x-y)
bài 2;tìm x hoặc y biết ;
a,2x.(x-5)-x(2x+3)=26
b,(3y2-y+1).(y-1)+y2.(4-3y)-\(\dfrac{5}{2}\)=0
c;2x2+3(x-1).(x+1)=5x(x+1)
Thực hiện phép tính :
a) \(\left(\dfrac{1}{2}x-1\right)\left(2x-3\right)\)
b) \(\left(x-7\right)\left(x-5\right)\)
c) \(\left(x-\dfrac{1}{2}\right)\left(x+\dfrac{1}{2}\right)\left(4x-1\right)\)
7. thực hiện phép tính
a)[\(\dfrac{1}{2}x-1\) ](2x-3) b) (x-7)(x-5)
c) [x-\(\dfrac{1}{2}\) ][x+\(\dfrac{1}{2}\) ] (4x-1)
Thực hiện phép tính :
a) \(\left(x^2-2x+3\right)\left(\dfrac{1}{2}x-5\right)\)
b) \(\left(x^2-2xy+y^2\right)\left(x-y\right)\)
Thực hiện phép tính
a) ( x - 1) ( x +1) ( x +2)
b) \(\dfrac{1}{2}\)x\(^2\)y\(^2\) ( 2x + y) ( 2x - y )
Cho x>0;y>0;x+y=2018
a)tìm GTLN của B=\(\dfrac{2x^2+8xy+2y^2}{x^2+2xy+y^2}\)
b)TÌm GTNN của C=\(\left(1+\dfrac{2012}{x}\right)^2+\left(1+\dfrac{2012}{y}\right)^2\)
