\(=7x^3-3x^2y-7x^2y+3xy^2+7x-3y\\ =7x^3-10x^2y+3xy^2+7x-3y\)
\(=7x^3-3x^2y-7x^2y+3xy^2+7x-3y\\ =7x^3-10x^2y+3xy^2+7x-3y\)
6). – x2 y(xy2 – 1/2 xy + 3/4 x2 y2 )
7). (3xy – x2 + y). 2/3 x2 y
8). (4x3 – 5xy + 2x)( – 1/2 xy)
9). 2x2 (x2 + 3x + 1/2 )
10). – 3/2 x4 y2 (6x4 − 10/9 x2 y3 – y5 )
11). 2 3 x3 (x + x2 – 3/4 x5 )
12). 2xy2 (xy + 3x2 y – 2/3 xy3 )
13). 3x(2x3 – 1/3 x2 – 4x)
14). 3/5 x3 y5 (7x4 + 5x2 y − 10/21 x4 y3 –y4 )
A= ( 4x - 5)(2x+3) - 4(x+2)(2x - 1)+(10x+7)
B=(7x - 6y)(4x+3y) - 2(14x+y)(x - 9y) - 19(13xy - 1)
1. Tìm đa thức C, biết: A=x2 - 2y + xy + 1
B=x2 + y - x2y2 - 1
a) C= A + B
b) C + A = B
Bài1:Làm tính nhân:
a) 2x. (x2– 7x -3) b) ( -2x3+ y2-7xy). 4xy2 c)(-5x3).(2x2+3x-5)
d)(x2-2x+3). (x-4) e) ( 2x3-3x -1). (5x+2) g) 3(2x-1)-5(x-3)
a, -2 x^3y(2x^2-3y+5yz)
b, (x-2y)(x^2y^2-xy+2y)
c, 2/5xy(x^2.y-5x+10y)
d, 2/3x^2y.(3xy-x^2+y)
e, (x-y)(x^2+xy+y^2)
f, (1/2xy-1).(x^3-2x-6)
\(\left(3x^3y-\dfrac{1}{2}x^2+\dfrac{1}{5}xy\right).6xy^3\)
1/ Thực hiện phép nhân :
a) x2 ( 5x3 - x - \(\dfrac{1}{2}\))
b) ( 3xy - x2 + y ) \(\dfrac{2}{3}\)x2y
c) x2 ( 4x3 - 5xy + 2x ) ( -\(\dfrac{1}{2}\) xy )
2/ Tìm x, biết
a) 3x( 12x - 4 ) - 9x (4x - 3 ) = 30
b ) x( 5 - 2x ) + 2x ( x - 1 )= 15
tính:
1. -4x5(x3-4x2+7x-3)
2. 3x4(-2x3+5x2-\(\dfrac{2}{3}\)x+\(\dfrac{1}{3}\))
3. -5x2y4(3x2y3-2x3y2-xy)
4. 4x3y2(-2x2y+4x4-3y2)
BÀI 1: NHÂN ĐƠN THỨC VỚI ĐA THỨC
11) \(\dfrac{1}{3}\)x2y2 ( 6x + \(\dfrac{2}{3}\)x2 - y)
12) \(\dfrac{3}{4}\)x3y2 ( 4x2y - x +y5 )
13) -5x2y4 ( 3x2y3 - 2x3y2 -xy)
Phân tích thành nhân tử :
1) -8x2 + 5x + 3
Phân tích đa thức thành nhân tử :
2) 6x2 + xy - 7x - 2y2 + 7y - 5