\(\left(x-\dfrac{1}{2}\right)\left(x+\dfrac{1}{2}\right)\left(4x-1\right)=\left(x^2-\dfrac{1}{4}\right)\left(4x-1\right)=4x^3-x^2-x+\dfrac{1}{4}\)
(x-1/2)(x+1/2)(4x-1)=(x2-1/4)(4x-1)=4x3-x2-x+1/4
\(\left(x-\dfrac{1}{2}\right)\left(x+\dfrac{1}{2}\right)\left(4x-1\right)=\left(x^2-\dfrac{1}{4}\right)\left(4x-1\right)=4x^3-x^2-x+\dfrac{1}{4}\)
(x-1/2)(x+1/2)(4x-1)=(x2-1/4)(4x-1)=4x3-x2-x+1/4
Tìm x
\(\dfrac{4}{5}x^2\left(\dfrac{x}{3}-\dfrac{1}{2}\right)-\left(\dfrac{1}{5}x-\dfrac{2}{3}\right)\left(\dfrac{4x^2}{3}+1\right)=\dfrac{22}{45}x^2\)
1) (\(\dfrac{1}{2}\)x + 3)*(x2- 4x- 6)
2) (6x2 -9x +15)*(\(\dfrac{2}{3}\)x+1)
3) (3x2 -x+5)*(x3+5x-1)
4) (x-1)*(x+1)*(x-2)
5) D=(x-7)*(x+5)-(x-4)*(x+3)
6) E= 4x*(x2-x-1)-(x+3)*(x2-2)
7) F= 5x*(x-3)*(x-1)-4x*(x2-2x)
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). \(\left(\dfrac{x^2+xy}{x^3+x^2y+xy^2+y^3}+\dfrac{y}{x^2+y^2}\right):\left(\dfrac{1}{x-y}-\dfrac{2xy}{x^3-x^2y+xy^2-y^3}\right)\)
Tìm x
\(\dfrac{4}{5}x^2\left(\dfrac{x}{3}-\dfrac{1}{2}\right)-\left(\dfrac{1}{5}x-\dfrac{2}{3}\right)\left(\dfrac{4x^2}{3}+1\right)=\dfrac{22}{45}x^2\)
MÌNH CẦN GẤP GIÚP MÌNH NHA
1) (x2-4x+16) (x+4)-x(x+1) (x+2)+3x2=0
2) (8x+2) (1-3x)+(6x-1) (4x-10)=-50
3) (x2+2x+4) (2-x)+x(x-3) (x+4)-x2+24=0
4) (\(\dfrac{x}{2}\)x2+3) (5-6x)+(12x-2) (\(\dfrac{x}{4}\)x4+3)=0
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) (x-1)(x+1)(x+2)
b) \(\dfrac{1}{2}x^2y^2\left(2x+y\right)\left(2x-y\right)\)
c)\(\left(x-\dfrac{1}{2}\right)\left(x+\dfrac{1}{2}\right)\left(4x-1\right)\)
Bài 1:
a) x (\(x^2\) + 2) + 2x\((1-\dfrac{1}{2}x^2)=4\)
b) (2x)\(^2\) (x – 1) + x(\(x^2\) + 4x) = 40
c) 3x(x – 2) – 3(\(x^2\) – 3) = 8
d) 2\(x^2\)(4\(x^3\) + 2x) + (\(x^2\) – 2)(- 2x)\(^3\) = 20
Bài 2:
P = 3x(\(\dfrac{2}{3}\)\(x^2\) − \(3x^4)\) + (3x)\(^2\) (\(x^3\) – 1) + (- 2x + 9)\(x^2\) - 12
Tính giá trị biểu thức sau:
A = x2 - 20x + 100 với x = 10.
B = 4x2 - 4xy + y2 với x = \(\dfrac{1}{2}\); y = 1.
C = 4x2 - 20x + 25 với x = \(\dfrac{5}{2}\).
D = 9y2 - 12y + 5 với x = \(\dfrac{1}{2}\); y = 1