Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Bài 1: 4a2-4ab+b2-9a2b2
=(2a)2-2.2a.b+b2-(3ab)2
=(2a-b)2-(3ab)2
=(2a-b-3ab)(2a-b+3ab)
a/ (4a2-4ab+b2)-9a2b2
= (2a-b)2-(3ab)2
= (2a-b-3ab) (2a-b+3ab)
a)\(x^2-6xy+9y^2=x^2-2\cdot x\cdot3y+\left(3y\right)^2=\left(x-3y\right)^2\)
b) \(\left(x^2+1\right)^2-4x^2\)
\(=\left(x^2+1+2x\right)\left(x^2+1-2x\right)\)
\(=\left(x+1\right)^2\left(x-1\right)^2\)
a)\(x^2-6xy+9y^2-25z^2=\left[x^2-2.x.3y+\left(3y\right)^2\right]-\left(5z\right)^2\)
\(=\left(x-3y\right)^2-\left(5z\right)^2=\left(x-3y-5z\right)\left(x-3y+5z\right)\)
b)\(xyz+x^2yz-6yz=yz\left(x^2+x-6\right)=yz\left(x^2+3x-2x-6\right)\)
\(=yz\left[x\left(x+3\right)-2\left(x+3\right)\right]=yz\left(x-2\right)\left(x+3\right)\)
a.x2-6xy+9y2-25z2
= ( x2-6xy+9y2)-25z2
= [x2-2x3y+(3y)2]-25z2
= (x-3y)2-252
= (x-3y+25)(x-3y-25)
a) 2x3 + 6xy - x2z - 3yz
= ( 2x3 + 6xy ) - ( x2z + 3yz )
= 2x( x2 + 3y ) - z( x2 + 3y )
= ( x2 + 3y )( 2x - z )
b) x2 - 6xy + 9y2 - 49
= ( x2 - 6xy + 9y2 ) - 49
= ( x - 3y )2 - 72
= ( x - 3y - 7 )( x - 3y + 7 )
c) x3 + 4x2 + 16x + 64
= ( x3 + 4x2 ) + ( 16x + 64 )
= x2( x + 4 ) + 16( x + 4 )
= ( x + 4 )( x2 + 16 )
a) =(2x^3-x^2z)+(6xy-3yz)
=x^2(2x-z)+3y(2x-z)
=(x^2+3y)(2x-z)
b) =(x^2-6xy+9y^2)-7^2
=(x-3y)^2-7^2
=(x-3y+7)(x-3y-7)
c) =(x^3+4x^2)+(16x+64)
=x^2(x+4)+16(x+4)
=(x^2+16)(x+4)
\(x^2+4x-9y^2+4\)
\(=\left(x^2+2.2x+2^2\right)-\left(3y\right)^2\)
\(=\left(x+2\right)^2-\left(3y\right)^2\)
\(=\left(x+2-3y\right)\left(x+2+3y\right)\)
\(x^2-9y^2-6y-1\)
\(=x^2-\left[\left(3y\right)^2+2.3y+1^2\right]\)
\(=x^2-\left(3y+1\right)^2\)
\(=\left(x-3y-1\right)\left(x+3y+1\right)\)
Tham khảo nhé~
a/Ta có:x2+4x-9y2+4
=x2+4x+4-(3y)2
=(x+2)2-(3y)2
=(x+2-3y)(x+2+3y)
b/Ta có:x2-9y2-6xy-1
=x2-6xy-(3y)2-1
=(x-3y-1)(x-3y+1)
a/ 9a^3 - 13a + 6 = 9a^3 - 6a^2 + 6a^2 - 4a - 9a + 6 = (9a^3 - 6a^2) + (6a^2 - 4a) - (9a - 6) = 3a^2(3a - 2) + 2a(3a - 2) - 3(3a - 2) = (3a^2 + 2a - 3)(3a - 2) Mình gửi luôn cho nóng^^Được câu nào hay câu đó. Yên tâm mình sẽ cố nghĩ &gửi nốt :)))
b/x^4 - 4x^3 + 8x + 3 = x^4 - 3x^3 - x^3 + 3x^2 - 3x^2 + 9x - x + 3 = (x^4 - 3x^3) - (x^3 - 3x^2) - (3x^2 - 9x) - (x - 3) = x^3(x - 3) - x^2(x - 3) - 3x(x - 3) - (x - 3) = (x^3 - x^2 - 3x - 1)(x - 3) Mình đang cố nghĩ nốt con c đây, có vẻ khó^^
a) ax + ay - bx - by = ( ax - bx ) + ( ay - by ) = x( a - b ) + y( a - b ) = ( a - b )( x + y ) < đã sửa >
b) 2x2 - 6xy + 5x - 15y = 2x( x - 3y ) + 5( x - 3y ) = ( x - 3y )( 2x + 5 )
c) ( a + b )2 - 4a2 = ( a + b )2 - ( 2a )2 = ( a + b - 2a )( a + b + 2a ) = ( b - a )( b + 3a )
d) 5a2xy - 10a3x - 15a2x2 = 5a2x( y - 2a - 3x )
e) 3( x - 1 ) + 5x( x - 1 ) = ( x - 1 )( 3 + 5x )
f) 9a2 - 4 = ( 3a )2 - 22 = ( 3a - 2 )( 3a + 2 )
g) 2x3 + 8x4 + 8x = 2x( x + 4x2 + 4 )
h) a2 - 4 + 4b - b2 = a2 - ( b2 - 4b + 4 ) = a2 - ( b - 2 )2 = ( a - b + 2 )( a + b - 2 )
i) a2 + 2ab + b2 - 16 = ( a2 + 2ab + b2 ) - 16 = ( a + b )2 - 42 = ( a + b - 4 )( a + b + 4 )
k) x2 + 5x + 4 = x2 + x + 4x + 4 = x( x + 1 ) + 4( x + 1 ) = ( x + 1 )( x + 4 )
l) 2x2 - 3x - 5 = 2x2 + 2x - 5x - 5 = 2x( x + 1 ) - 5( x + 1 ) = ( x + 1 )( 2x - 5 )
m) x3 + 6x2 + 9x = x( x2 + 6x + 9 ) = x( x + 3 )2
x^2+6xy+9y^2-3x-9y+2
=( x^2+6xy+9y^2)-3(x+3y)+9/4 -1/4
=(x+3y)^2-3(x+3y)+(3/2)^2- 1/4
=(x+3y+3/2)^2-(1/2)^2
=(x+3y+3/2+1/2)(x+3y+3/2-1/2)=(x+3y+2)(x+3y+1)
1) ta có : \(x^2-4-6xy+9y^2=\left(x-3y\right)^2-2^2=\left(x-3y+2\right)\left(x-3y-2\right)\)
2) ta có : \(9a^2+6ab+b^2-49x^2=\left(3a+b\right)^2-\left(7x\right)^2=\left(3a+b-7x\right)\left(3a+b+7x\right)\)
3) ta có : \(b^4+4a^4=b^4+4a^2b^2+4a^4-4a^2b^2=\left(b^2+2a^2\right)^2-\left(2ab\right)^2\)
\(=\left(b^2+2a^2-2ab\right)\left(b^2+2a^2+2ab\right)\)