1/5x3/4-1/2x3/5
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)
\(a,=2x^3-14x^2-6x\\ b,=-8x^4y^2+4xy^4-28x^2y^3\\ c,=-10x^5-15x^4+25x^3\\ d,=x^3-4x^2-2x^2+8x+3x-12=x^3-6x^2+11x-12\\ e,=10x^4+4x^3-15x^2-6x-5x-2=10x^4+4x^3-15x^2-11x-2\\ g,=6x-3-5x+15=x+12\)
Bài 1: Làm tính nhân:
a) 2x. (x2 – 7x -3) b) ( -2x3 + y2 -7xy). 4xy2
c)(-5x3). (2x2+3x-5) d) (2x2 - xy+ y2).(-3x3)
e)(x2 -2x+3). (x-4) f) ( 2x3 -3x -1). (5x+2)
g) ( 25x2 + 10xy + 4y2). ( ( 5x – 2y) h) ( 5x3 – x2 + 2x – 3). ( 4x2 – x + 2)
a) \(2x\left(x^2-7x-3\right)=2x.x^2-2x.7x-2x.3=2x^3-14x^2-6x\)
b) \(\left(-2x^3+y^2-7xy\right)4xy^2=\left(-2x^3\right)4xy^2+y^24xy^2-7xy.4xy^2=-8x^4y^2+4xy^4-28x^2y^3\)
c) \(\left(-5x^3\right)\left(2x^2+3x-5\right)=-5x^32x^2-5x^33x-5x^3.-5=-10x^5-15x^4+25x^3\)
d) \(\left(2x^2-xy+y^2\right)\left(-3x^3\right)=-3x^32x^2-3x^3.-xy-3x^3y^2=-6x^5+3x^4y-3x^3y^2\)
e) \(\left(x^2-2x+3\right)\left(x-4\right)=x\left(x^2-2x+3\right)-4\left(x^2-2x+3\right)=x^3-2x^2+3x-4x^2+8x-12=x^3-6x^2+11x-12\)
f) \(\left(2x^3-3x-1\right)\left(5x+2\right)=5x\left(2x^3-3x-1\right)+2\left(2x^3-3x-1\right)=10x^4-15x^2-5x+4x^3-6x-2=10x^4+4x^3-15x^2-11x-2\)
g)
\(\left(25x^2+10xy+4y^2\right).\left((5x-2y\right)\)
\(=125x^3-50x^2y+20x^2y-20xy^2+20xy^2-8y^3\)
\(=125x^3-30x^2y+8y^3\)
h)
\(\left(5x^3-x^2+2x-3\right)\left(4x^2-x+2\right)\)
\(=20x^5-5x^4+10x^3-4x^4+x^3-2x^2+8x^3-2x^2+4x-12x^2+3x-6\)
\(=20x^5-9x^4+19x^3-16x^2+7x-6\)
Làm tính nhân :
a) 2x. (x2 – 7x -3)
b) ( -2x3 + y2 -7xy). 4xy2
c)(-5x3).(2x2+3x-5)
d) (2x2 - xy+ y2).(-3x3)
e)(x2 -2x+3). (x-4) f) ( 2x3 -3x -1). (5x+2)
a: \(=2x^3-14x^2-6x\)
c: \(=-10x^5-15x^4+25x^3\)
a) 2x. (x2 – 7x -3)
= 2x3- 14x2- 6x
b) ( -2x3 + y2 -7xy). 4xy2
= -8x4y2+ 4xy4- 28x2y3
c)(-5x3).(2x2+3x-5)
= -10x5-15x4+25x3
d) (2x2 - xy+ y2).(-3x3)
=-6x5+ 3x4y -3x3y2
e)(x2 -2x+3). (x-4)
=x3-2x2+3x -4x2+8x-12
=x3-6x2+11x-12
f) ( 2x3 -3x -1). (5x+2)
=10x4-15x2-5x +4x3-6x-2
=10x4+4x3-15x2-11x-2
Bài 1: Thực hiện phép tính
a)5x3(3x2 – 5x + 3) c)x2 ( 2x3 – 4x + 3)
b) -1\(\dfrac{1}{2}\)x22x – 1)(x2 + 5x – 4) d) (3x – 4)(2x + 4) + (5 – x)(2x2 + 3x – 2)
a: \(=15x^5-25x^4+15x^3\)
b: \(=2x^3+10x^2-8x-x^2-5x+4\)
\(=2x^3+9x^2-13x+4\)
a) 2x. (x2 – 7x -3)
b) ( -2x3 + y2 -7xy). 4xy2
c)(-5x3). (2x2+3x-5)
d) (2x2 - xy+ y2).(-3x3)
e)(x2 -2x+3). (x-4)
f) ( 2x3 -3x -1). (5x+2)
g) ( 25x2 + 10xy + 4y2). ( 5x – 2y)
h) ( 5x3 – x2 + 2x – 3). ( 4x2 – x + 2)
a,\(4x^2-14x^2-6x=-10x^2-6x\)
các câu còn lại làm tg tuj
a) 2x.(x2 - 7x - 3)
= 2xx2 + 2x(-7x) + 2x(-3)
= 2x2x - 2.7xx - 2.3x
= 2x3 - 14x2 - 6x
a) 2x. (x2 – 7x -3)
b) ( -2x3 + y2 -7xy). 4xy2
c)(-5x3). (2x2+3x-5)
d) (2x2 - xy+ y2).(-3x3)
e)(x2 -2x+3). (x-4)
f) ( 2x3 -3x -1). (5x+2)
mk cần gấp lắm nhanh hộ mk nhé!
a) \(2x\left(x^2-7x-3\right)=2x^3-14x^2-6x\)
b) \(\left(-2x^3+y^2-7xy\right)\cdot4xy^2=-8x^4y^2+4xy^4-28x^2y^3\)
c) \(\left(-5x^3\right)\left(2x^2+3x-5\right)=-10x^5-15x^4+25x^3\)
d) \(\left(2x^2-xy+y^2\right)\left(-3x^3\right)=-6x^5+3x^4y-3x^3y^2\)
e) \(\left(x^2-2x+3\right)\left(x-4\right)=x^3-4x^2-2x^2+8x+3x-12=x^3-6x^2+11x-12\)
f) \(\left(2x^3-3x-1\right)\cdot\left(5x+2\right)=5x\left(2x^3-3x-1\right)+2\left(2x^3-3x-1\right)=10x^4-15x^2-5x+4x^3-6x-2=10x^4+4x^3-15x^2-11x-2\)
a) 2x. (x2 – 7x -3)
c) (-5x3).(2x2+3x-5)
e) (x2 -2x+3). (x-4)
f) ( 2x3 -3x -1). (5x+2)
Thực hiện phép chia:
1. (-3x3 + 5x2 - 9x + 15) : ( 3x + 5)
2. ( 5x4 + 9x3 - 2x2 - 4x - 8) : ( x-1)
3. ( 5x3 + 14x2 + 12x + 8 ) : (x + 2)
4. ( x4 - 2x3 + 2x -1 ) : ( x2 - 1)
5. ( 5x2 - 3x3 + 15 - 9x ) : ( 5 - 3x)
6. ( -x2 + 6x3 - 26x + 21) : ( 3 -2x )
1: Sửa đề: 3x-5
\(=\dfrac{-x^2\left(3x-5\right)-3\left(3x-5\right)}{3x-5}=-x^2-3\)
2: \(=\dfrac{5x^4-5x^3+14x^3-14x^2+12x^2-12x+8x-8}{x-1}\)
=5x^2+14x^2+12x+8
3: \(=\dfrac{5x^3+10x^2+4x^2+8x+4x+8}{x+2}=5x^2+4x+4\)
4: \(=\dfrac{\left(x^2-1\right)\left(x^2+1\right)-2x\left(x^2-1\right)}{x^2-1}=x^2+1-2x\)
5: \(=\dfrac{x^2\left(5-3x\right)+3\left(5-3x\right)}{5-3x}=x^2+3\)
Phân tích đa thức thành nhân tử:
a) ( x - 1 )x + ( x - 1 )y
b) 5x3 + 15xy
c) 6xy2 - 8x2yy
d) 2x3 + 4x2 - 6x
e) 5( x - 3 ) - 20( 3 - x )
\(a)(x-1)x+(x-1)y\)
\(=(x-1)(x+y)\)
\(b)5x^3+15xy\)
\(=5x(x^2+3y)\)
\(c)6xy^2-8x^2y\)
\(=2xy(3y-4x)\)
\(d)2x^3+4x^2-6x\)
\(=2x(x^2+2x-3)\)
\(e)5(x-3)-20(3-x)\)
\(=5(x-3)+20(x-3)\)
\(=(x-3)(5+20)\)
\(=25(x-3)\)
a: =(x-1)(x+y)
b: =5x(x^2+3y)
c: 6xy^2-8x^2y=2xy(3y-4x)
d: =2x(x^2+2x-3)
=2x(x+3)(x-1)
e: =25(x-3)