phân tích đa thức thành nhân tử
A) x mũ 2 + 2x + 1 -4y mũ 2
B) x mũ 3 - 2x mũ 2 + 5x - 1 Chia cho x-5
phân tích đa thức sau thành nhân tử
1, x mũ 2 + 4xy + 4y mũ 2
2, 4x mũ 2 - 36y mũ 2
3, x mũ 3 - 2x mũ 2 + 5x - 10
4, a mũ 3 + a mũ 2 + 3a + 3
5, 7x mũ 3 - 21x mũ 2 + 3 - x
1 x mũ 2 + 4xy + 4y mũ 2 = x^2 + 4xy + 4y^2 =(2y+x)^2
2, 4x mũ 2 - 36y mũ 2 =4x^2 -36y^2 = -4 (3y-x) (3y+x)
1, \(x^2+4xy+4y^2=\left(x+2y\right)^2\)
2, \(4x^2-36y^2=\left(2x-6y\right)\left(2x+6y\right)\)
3, \(x^3-2x^2+5x-10=x^2\left(x-2\right)+5\left(x-2\right)=\left(x^2+5\right)\left(x-2\right)\)
4, \(a^3+a^2+3a+3=a^2\left(a+1\right)+3\left(a+1\right)=\left(a^2+3\right)\left(a+1\right)\)
5, \(7x^3-21x^2+3-x=7x^2\left(x-3\right)-\left(x-3\right)=\left(7x^2-1\right)\left(x-3\right)\)
phân tích đa thức sau thành nhân tử
a, 5x mũ 2 + 10xy + 5y mũ 2
b, x mũ 2 + 3x - y mũ 2 + 3y
c, x mũ 2 + 5x - y mũ 2 + 5y
d, 3x mũ 2 - 3y mũ 2 - 2( x - y) mũ 2
e, x mũ 2 - 2x - 4y mũ 2 - 4y
Trả lời:
a, 5x2 + 10xy + 5y2 = 5 ( x2 + 2xy + y2 ) = 5 ( x + y )2
b, x2 + 3x - y2 + 3y = ( x2 - y2 ) + ( 3x + 3y ) = ( x - y )( x + y ) + 3 ( x + y ) = ( x + y )( x - y + 3 )
c, x2 + 5x - y2 + 5y = ( x2 - y2 ) + ( 5x + 5y ) = ( x - y )( x + y ) + 5 ( x + y ) = ( x + y )( x - y + 5 )
d, 3x2 - 3y2 - 2 ( x - y )2 = 3 ( x2 - y2 ) - 2 ( x - y )2 = 3 ( x - y )( x + y ) - 2 ( x - y )2 = ( x - y )[ 3 ( x + y ) - 2 ] = ( x - y )( 3x + 3y - 2 )
e, x2 - 2x - 4y2 - 4y = ( x2 - 4y2 ) - ( 2x + 4y ) = ( x - 2y )( x + 2y ) - 2 ( x + 2y ) = ( x + 2y )( x - 2y - 2 )
a) 5x2+10xy+5y2
=5(x2+2xy+y2)
=5(x+y)2
b) x2+3x-y2+3y
=(x2-y2)+(3x+3y)
=(x-y)(x+y)+3(x+y)
=(x+y)(x-y+3)
c) x2+5x-y2+5y
=(x2-y2)+(5x+5y)
=(x-y)(x+y)+5(x+y)
=(x+y)(x-y+5)
d) 3x2-3y2-2(x-y)2
=3(x2-y2)-2(x-y)2
=3(x-y)(x+y)-2(x-y)2
=(x-y)[3(x+y)-2(x-y)]
e) x2-2x-4y2-4y
=(x2-4y2)-(2x+4y)
=(x-2y)(x+2y)-2(x+2y)
=(x+2y)(x-2y-2)
#H
phân tích đa thức sau thành nhân tử
1, x mũ 2 - y mũ 2 + 4x + 4
2, x mũ 2 + 2x - 4y mũ 2 - 4y
3, 3x mũ 2 - 4y + 4x - 3y mũ 2
4, x mũ 4 - 6x mũ 3 + 54x - 81
bài 48; phân tích các đa thức sau thành nhân tử
5, x mũ 2 - y mũ 2 + 4x + 4
6, x mũ 2 + 2x - 4y mũ 2 - 4y
7, 3x mũ 2 - 4y + 4x - 3y mũ 2
8, x mũ 4 - 6x mũ 3 + 54x - 81
Trả lời:
5, x2 - y2 + 4x + 4
= ( x2 + 4x + 4 ) - y2
= ( x + 2 )2 - y2
= ( x + 2 - y ) ( x + 2 + y )
6, x2 + 2x - 4y2 - 4y
= ( x2 - 4y2 ) + ( 2x - 4y )
= ( x - 2y ) ( x + 2y ) + 2 ( x - 2y )
= ( x - 2y ) ( x + 2y + 2 )
7, 3x2 - 4y + 4x - 3y2
= ( 3x2 - 3y2 ) + ( 4x - 4y )
= 3 ( x2 - y2 ) + 4 ( x - y )
= 3 ( x - y ) ( x + y ) + 4 ( x - y )
= ( x - y ) [ 3 ( x + y ) + 4 ]
= ( x - y ) ( 3x + 3y + 4 )
8, x4 - 6x3 + 54x - 81
= ( x4 - 81 ) - ( 6x3 - 54x )
= ( x2 - 9 ) ( x2 + 9 ) - 6x ( x2 - 9 )
= ( x2 - 9 ) ( x2 + 9 - 6x )
= ( x - 3 ) ( x + 3 ) ( x - 3 )2
= ( x - 3 )3 ( x + 3 )
a, \(x^2-y^2+4x+4=\left(x+2\right)^2-y^2=\left(x+2-y\right)\left(x+2+y\right)\)
b, \(x^2+2x-4y^2-4y=\left(x-2y\right)\left(x+2y\right)+2\left(x-2y\right)=\left(x-2y\right)\left(x+2+2y\right)\)
c, \(3x^2-4y+4x-3y^2=3\left(x-y\right)\left(x+y\right)-4\left(y-x\right)=\left(x-y\right)\left(3x+3y+4\right)\)
d, \(x^4-6x^3+54x-81=\left(x^2+9\right)\left(x-3\right)\left(x+3\right)-6x\left(x^2-9\right)\)
\(=\left(x-3\right)\left(x+3\right)\left(x^2-6x+9\right)=\left(x-3\right)^3\left(x+3\right)\)
5, x2-y2+4x+4
=(x2+4x+4)-y2
=(x+2)2-y2
=(x+2-y)(x+2+y)
6, x2+2x-4y2-4y
=(x2-4y2)+(2x-4y)
=(x-2y)(x+2y)+2(x-2y)
=(x-2y)(x+2y+2)
7, 3x2-4y+4x-3y2
=(3x2-3y2)+(4x-4y)
=3(x2-y2)+4(x-y)
=3(x-y)(x+y)+4(x-y)
=(x-y)[3(x+y)+4]
=(x-y)(3x+3y+4)
8, x4-6x3+54x-81
=(x4-81)-(6x3-54x)
=(x2-9)(x2+9)-6x(x2-9)
=(x2-9)(x2+9-6x)
=(x+3)(x-3)(x-3)2
=(x+3)(x-3)3
#H
bài 2; phân tích các đa thức sau thành nhân tử
1, x mũ 2 - y mũ 2+ 4x 4
2, x mũ 2 + 2x - 4y mũ 2 - 4y
3, 3x mũ 2 - 4y + 4x - 3y mũ 2
4, x mũ 4 - 6x mũ 3 + 54x - 81
\(1,x^2-y^2+4x-4y\)
\(\left(x-y\right)\left(x+y\right)+4\left(x-y\right)\)
\(\left(x-y\right)\left(x+y+4\right)\)
\(x^2+2x-4y^2-4y\)
\(\left(x-2y\right)\left(x+2y\right)+2\left(x-2y\right)\)
\(\left(x-2y\right)\left(x+2y+2\right)\)
\(3,3x^2-4y+4x-3y^2\)
\(3\left(x^2-y^2\right)-4\left(x-y\right)\)
\(3\left(x-y\right)\left(x+y\right)-4\left(x-y\right)\)
\(\left(x-y\right)\left(3x+3y-4\right)\)
\(x^4-6x^3+54x-81\)
\(x^4+3x^3-9x^3+27x^2-27x^2+81x-27x-81\)
\(\left(x^4+3x^3\right)-\left(9x^3+27x^2\right)+\left(27x^2+81x\right)-\left(27x+81\right)\)
\(x^3\left(x+3\right)-9x^2\left(x+3\right)+27x\left(x+3\right)-27\left(x+3\right)\)
\(\left(x+3\right)\left(x^3-9x^2+27x-27\right)\)
\(\left(x+3\right)\left(x-3\right)^3\)
bài 1:thực hiện phép tính:
a)(2x mũ 4-x mũ 3+5x-6x mũ 2-1):(1-2x)
b)(x-2)(x mũ 2-2x+4)
bài 2:phân tích đa thức thành nhân từ:
a)5x mũ 2-10xy+5y mũ 2
b)x mũ 2-4x+4-y mũ 2
c)3x mũ 2-2x-5
giải giùm mình vs nhé các bạn, hiện tại mình đang rấp gấp
a, \(5x^2-10xy+5y^2=5\left(x^2-2xy+y^2\right)=5.\left(x-y\right)^2\)
b, \(x^2-4x+4-y^2=\left(x^2-4x+4\right)-y^2=\left(x-2\right)^2-y^2\)
\(=\left(x-2-y\right)\left(x-2+y\right)\)
c, \(3x^2-2x-5=3x^2-5x+3x-5=x\left(3x-5\right)+3x-5\)
\(=\left(3x-5\right)\left(x+1\right)\)
bài 1; phân tích các đa thức sau thành nhân tử
1, x mũ 2( x - 3 )- 4x + 12
2, 2a(x + y) - x - y
3, 2x - 4 + 5x mũ 2 - 10x
4, 5x mũ 2 - 12x - 7x + 14
5, xy - y mũ 2 - 3x + 3y
1, \(x^2\left(x-3\right)-4x+12=x^2\left(x-3\right)-4\left(x-3\right)\)
\(=\left(x-2\right)\left(x+2\right)\left(x-3\right)\)
2, \(2a\left(x+y\right)-x-y=2a\left(x+y\right)-\left(x+y\right)=\left(2a-1\right)\left(x+y\right)\)
3, \(2x-4+5x^2-10x=2\left(x-2\right)+5x\left(x-2\right)=\left(2+5x\right)\left(x-2\right)\)
4, sửa đề :
\(6x^2-12x-7x+14=6x\left(x-2\right)-7\left(x-2\right)=\left(6x-7\right)\left(x-2\right)\)
5, \(xy-y^2-3x+3y=y\left(x-y\right)-3\left(x-y\right)=\left(y-3\right)\left(x-y\right)\)
a) x2(x-3)-4x+12
=x2(x-3)-4(x-3)
=(x-3)(x2-4)
=(x-3)(x-2)(x+2)
b) 2a(x+y)-x-y
=2a(x+y)-(x+y)
=(x+y)(2a-1)
c) 2x-4+5x2-10x
=2(x-2)+5x(x-2)
=(x-2)(2+5x)
d) 5x2-12x-7x+14
=5x2-19x+14
e) xy-y2-3x+3y
=y(x-y)-3(x-y)
=(x-y)(y-3)
#H
Trả lời:
1, x2 ( x - 3 ) - 4x + 12 = x2 ( x - 3 ) - 4 ( x - 3 ) = ( x - 3 )( x2 - 4 ) = ( x - 3 )( x - 2 )( x + 2 )
2, 2a ( x + y ) - x - y = 2a ( x + y ) - ( x + y ) = ( x + y )( 2a - 1 )
3, 2x - 4 + 5x2 - 10x = ( 2x - 4 ) + ( 5x2 - 10x ) = 2 ( x - 2 ) + 5x ( x - 2 ) = ( x - 2 )( 2 + 5x )
4, Sửa đề: 6x2 - 12x - 7x + 14 = ( 6x2 - 12x ) - ( 7x - 14 ) = 6x ( x - 2 ) - 7 ( x - 2 ) = ( x - 2 )( 6x - 7 )
5, xy - y2 - 3x + 3y = ( xy - y2 ) - ( 3x - 3y ) = y ( x - y ) - 3 ( x - y ) = ( x + y )( y - 3 )
bài 1; phân tích các đa thức sau thành nhân tử
6, x mũ 2 y + xy mũ 2 - 4x - 4y
7, 10ax - 5ay - 2x + y
8, x mũ 3 - 2x mũ 2 + 2a - 4
9, 4x mũ 2 - y mũ 2 + 8y - 16
6, \(x^2y+xy^2-4x-4y=xy\left(x+y\right)-4\left(x+y\right)=\left(xy-4\right)\left(x+y\right)\)
7, \(10ax-5ay-2x+y=5a\left(2x-y\right)-\left(2x-y\right)=\left(5a-1\right)\left(2x-y\right)\)
8, xem lại đề bạn nhé
9, \(4x^2-y^2+8y-16=4x^2-\left(y^2-8y+16\right)=4x^2-\left(y-4\right)^2\)
\(=\left(2x-y+4\right)\left(2x+y-4\right)\)
Trả lời:
6, x2y + xy2 - 4x - 4y = ( x2y + xy2 ) - ( 4x + 4y ) = xy ( x + y ) - 4 ( x + y ) = ( x + y )( xy - 4 )
7, 10ax - 5ay - 2x + y = ( 10ax - 5ay ) - ( 2x - y ) = 5a ( 2x - y ) - ( 2x - y ) = ( 2x - y )( 5a - 1 )
8, Sửa đề: x3 - 2x2 + 2x - 4 = ( x3 - 2x2 ) + ( 2x - 4 ) = x2 ( x - 2 ) + 2 ( x - 2 ) = ( x - 2 )( x2 + 2 )
9, 4x2 - y2 + 8y - 16 = 4x2 - ( y2 - 8y + 16 ) = 4x2 - ( y - 4 )2 = ( 2x - y + 4 )( 2x + y - 4 )
Bài 1: Phân tích các đa thức sau thành nhân tử. 7) (xy + 4) mũ 2 – (2x + 2y) mũ 2 8) 81x mũ 2 – 64y mũ 2 9) (a mũ 2 + b mũ 2 + 5) mũ 2 - 4 (ab + 2) mũ 2 10) (x – 1) mũ 2 – (x + 1) mũ 2 11) 8x mũ 3 - 1/8 12) 1/25x mũ 2 - 64y mũ 2 13) x mũ 3 + 1/27