\(2x\left(3x^2-7x+2\right)\)
\(=6x^3-14x^2+4x\)
\(\left(x-2\right)\left(3x^2+2x+4\right)\)
\(=3x^3+\left(-4x^2\right)+\left(-8\right)\)
\(\left(3x^2y^2+6x^2y^3-12xy\right)\div3xy\)
\(=xy+2xy-4\)
x^2/x-2+4-4x/x-2 ???
1) 2x(3x^2-7x+2)
<=> \(6x^3-14x^2+4x\)
2) (x-2)(3x^2+2x+4)
<=> \(3x^3-4x^2-8\)
3) (3x^2y^2+6x^2y^3-12xy)÷3xy
<=> xy + 2xy2 -4
4) X^2/x-2+4-4x/x-2
<=> \(\dfrac{x^2-4x+4}{x-2}=\dfrac{\left(x-2\right)^2}{x-2}=x-2\)
*2x(3x2-7x+2)
=6x3-14x2+4x
*(x-2)(3x2+2x+4)
=3x3+2x2+4x-6x2-4x-8
=3x3-4x2-8
*(3x2y2+6x2y3-12xy)÷3xy
=xy+2xy2-4
*x2/x-2+4-4x/x-2
(mk ko bt)
Câu 1: Thực hiện phép tính
a) Ta có: \(2x\cdot\left(3x^2-7x+2\right)\)
\(=2x\cdot3x^2-2x\cdot7x+2x\cdot2\)
\(=6x^3-14x^2+4x\)
b) Ta có: \(\left(x-2\right)\left(3x^2+2x+4\right)\)
\(=x\cdot3x^2+x\cdot2x+x\cdot4-2\cdot3x^2-2\cdot2x-2\cdot4\)
\(=3x^3+2x^2+4x-6x^2-4x-8\)
\(=3x^3-4x^2-8\)
c) Ta có: \(\left(3x^2y^2+6x^2y^3-12xy\right):3xy\)
\(=3x^2y^2:3xy+6x^2y^3:3xy-12xy:3xy\)
\(=xy+2xy^2-4\)
d) Ta có: \(\dfrac{x^2}{x-2}+\dfrac{4-4x}{x-2}\)
\(=\dfrac{x^2-4x+4}{x-2}\)
\(=\dfrac{\left(x-2\right)^2}{x-2}\)
\(=x-2\)
1. 6x3 - 14x2 + 4x
2. 3x3 - 4x2 - 8
3. xy + 2xy2 - 4
Câu3.cho bieu thuc
P=(1/x-1+1/x^2-x):x+1/(x-1)^2
A)tìm đk của x đều biểu thức p x định
B)RÚT GỌN BIỂU THỨC P
C)TÌM X ĐỂ P =2/3
