K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

15 tháng 7 2021
Kết bạn nha
15 tháng 7 2021

\(a,y^4-14y^2+49\)

\(\left(y^2-7\right)^2\)

\(b,x^2-2\)

\(x^2-\left(\sqrt{2}\right)^2=\left(x-\sqrt{2}\right)\left(x+\sqrt{2}\right)\)

\(c,y^2-13\)

\(y^2-\left(\sqrt{13}\right)^2=\left(y-\sqrt{13}\right)\left(y+\sqrt{13}\right)\)

\(d,-4x^2+9y^2\)

\(\left(3y\right)^2-\left(2x\right)^2\)

\(\left(3y-2x\right)\left(3y+2x\right)\)

2 tháng 10 2020

a) ( 4x2 - 3x - 18 )2 - ( 4x2 + 3x )2

= [ ( 4x2 - 3x - 18 ) - ( 4x2 + 3x ) ][ ( 4x2 - 3x - 18 ) + ( 4x2 + 3x ) ]

= ( 4x2 - 3x - 18 - 4x2 - 3x )( 4x2 - 3x - 18 + 4x2 + 3x )

= ( -6x - 18 )( 8x2 - 18 )

= -6( x + 3 ).2( 4x2 - 9 )

= -12( x + 3 )( 2x - 3 )( 2x + 3 )

b) 9( x + y - 1 )2 - 4( 2x + 3y + 1 )2

= 32( x + y - 1 )2 - 22( 2x + 3y + 1 )2

= [ 3( x + y - 1 ) ]2 - [ 2( 2x + 3y + 1 ) ]2

= ( 3x + 3y - 3 )2 - ( 4x + 6y + 2 )2

= [ ( 3x + 3y - 3 ) - ( 4x + 6y + 2 ) ][ ( 3x + 3y - 3 ) + ( 4x + 6y + 2 ) ]

= ( 3x + 3y - 3 - 4x - 6y - 2 )( 3x + 3y - 3 + 4x + 6y + 2 )

= ( -x - 3y - 5 )( 7x + 9y - 1 )

c) -4x2 + 12xy - 9y2 + 25

= 25 - ( 4x2 - 12xy + 9y2 )

= 52 - ( 2x - 3y )2

= [ 5 - ( 2x - 3y ) ][ 5 + ( 2x - 3y ) ]

= ( 5 - 2x + 3y )( 5 + 2x - 3y )

d) x2 - 2xy + y2 - 4m2 + 4mn - n2

= ( x2 - 2xy + y2 ) - ( 4m2 - 4mn + n2 )

= ( x - y )2 - ( 2m - n )2

= [ ( x - y ) - ( 2m - n ) ][ ( x - y ) + ( 2m - n ) ]

= ( x - y - 2m + n )( x - y + 2m - n )

27 tháng 9 2019

\(\left(x-y+4\right)^2-\left(2x+3y-1\right)^2\)

\(=\left(x-y+4+2x+3y-1\right)\left(x-y+4-2x-3y+1\right)\)

\(=\left(3x+2y+3\right)\left(-x-4y+5\right)\)

27 tháng 9 2019

\(49\left(y-4\right)^2-9y^2-36y-36\)

\(=49\left(y-4\right)^2-\left(9y^2+36y+36\right)\)

\(=49\left(y-4\right)^2-\left(3y+6\right)^2\)

\(=[7\left(y-4\right)]^2-\left(3y+6\right)^2\)

\(=\left(7y-28\right)^2-\left(3y+6\right)^2\)

\(=\left(7y-28+3y+6\right)\left(7y-28-3y-6\right)\)

\(=\left(10y-22\right)\left(4y-34\right)\)

Bài 1

a, x2 + 4x + 3

24 tháng 8 2019

a) \(x^2+4x+3\)

\(=x^2+3x+x+3\)

\(=x\left(x+3\right)+\left(x+3\right)\)

\(=\left(x+1\right)\left(x+3\right)\)

a) 4x2-1=(2x)2-12=(2x-1)(2x+1)

b)25x2-0.09=(5x)2-\(\left(\frac{3}{10}\right)^2\)=\(\left(5x-\frac{3}{10}\right)\left(5x+\frac{3}{10}\right)\)

c)9x2-14=(3x)2-\(\sqrt{14}^2\)=(3x-\(\sqrt{14}\))(3x+\(\sqrt{14}\))

d) (x-y)2-4=(x-y)2-22=(x-y-2)(x-y+2)

e) 9-(x-y)2=33-(x-y)2=(3-x+y)(3+x-y)

f)(x2+4)2-16x2=(x2+4)2-(4x)2=(x2+4+4x)(x2+4-4x)

Chúc hok tốt!!!

22 tháng 7 2018

\(a,\)\(4x^2-1\)\(=\left(2x\right)^2-1^2=\left(2x+1\right)\left(2x-1\right)\)

\(b,\)\(25x^2-0,09=\left(5x\right)^2-0,3^2=\left(5x-0,3\right)\left(5x+0,3\right)\)

\(c,\)\(9x^2-14=\left(3x\right)^2-\left(\sqrt{14}\right)^2=\left(3x-\sqrt{14}\right)\left(3x+\sqrt{14}\right)\)

\(d,\)\(\left(x-y\right)^2-4=\left(x-y\right)^2-2^2=\left(x-y+2\right)\left(x-y-2\right)\)

\(e,\)\(9-\left(x-y\right)^2=3^2-\left(x-y\right)^2=\left(3-x+y\right)\left(3+x-y\right)\)

\(f,\)\(\left(x^2+4\right)^2-16x^2=\left(x^2+4\right)^2-\left(4x\right)^2=\left(x^2+4-4x\right)\left(x^2+4+4x\right)\)

                                             \(=\left(x^2-2.2x+2^2\right)\left(x^2+2.2x+2^2\right)\)

                                               \(=\left(x-2\right)^2\left(x+2\right)^2\)

22 tháng 1 2021

a) a3 - a2c + a2b - abc

= a( a2 - ac + ab - bc )

= a[ a( a - c ) + b( a - c ) ]

= a( a - c )( a + b )

b) ( x2 + 1 )2 - 4x2

= ( x2 + 1 )2 - ( 2x )2

= ( x2 - 2x + 1 )( x2 + 2x + 1 )

= ( x - 1 )2( x + 1 )2

c) x2 - 10x - 9y2 + 25

= ( x2 - 10x + 25 ) - 9y2

= ( x - 5 )2 - ( 3y )2

= ( x - 3y - 5 )( x + 3y - 5 )

d) 4x2 - 36x + 56

= 4( x2 - 9x + 14 )

= 4( x2 - 7x - 2x + 14 )

= 4[ x( x - 7 ) - 2( x - 7 ) ]

= 4( x - 7 )( x - 2 )

22 tháng 1 2021

a,\(a^3-a^2c+a^2b-abc\)

\(=a\left(a^2-ac+ab-bc\right)\)

\(=a\left[a\left(a-c\right)+b\left(a-c\right)\right]\)

\(=a\left(a-b\right)\left(a-c\right)\)

b,\(\left(x^2+1\right)^2-4x^2\)

\(=\left(x^2+1-2x\right)\left(x^2+1+2x\right)\)

\(=\left(x-1\right)^2\left(x+1\right)^2\)

c,\(x^2-10x-9y^2+25\)

\(=\left(x^2-10x+25\right)-9y^2\)

\(=\left(x-5\right)^2-\left(3y\right)^2\)

\(=\left(x-5-3y\right)\left(x-5+3y\right)\)

d,\(4x^2-36x+56\)

\(=4\left(x^2-9x+14\right)\)

\(=4\left(x^2-7x-2x+14\right)\)

\(=4\left(x-7\right)\left(x-2\right)\)

10 tháng 7 2019

\(A=\left(6x-3y\right)+\left(4x^2-4xy+y^2\right)\) 

  \(=3\left(2x-y\right)+\left(2x-y\right)^2\) 

  \(=\left(3+2x-y\right)\left(2x-y\right)\)

\(B=9x^2-\left(y^2-4y+4\right)\) 

   \(=9x^2-\left(y-2\right)^2\) 

   \(=\left(3x+y-2\right)\left(3x-y+2\right)\)

10 tháng 7 2019

A = ( 6x - 3y ) + (4x2 - 4xy + y2 )

A = 3.( 2x - y) + [ ( 2x )2 - 2.2.x.y + y2 ]

A = 3.( 2x - y ) + ( 2x - y )2

A = ( 2x - y ).(3 + 2x - y )

B = 9x2 - ( y2 - 4y + 4 )

B = ( 3x )2 - ( y - 2 )2

B = ( 3x - y + 2 ).( 3x + y - 2 )

C = - 25x2 + y2 - 6y + 9

C =   ( y2 - 2.3.y + 3) - ( 5x )2

C = ( y - 3 )2 - ( 5x )2

C = (y - 3 - 5x ).( y - 3 +5x )

D = x2 - 4x - y2 -- 8y  - 12

D = ( x2 - 4x + 4 ) - 4 - y2 - 8y -12

D = ( x - 2.2x + 22 ) - ( y2 + 2.4.y + 42 )

D = ( x - 2 )2 - ( y + 4 )2

D = ( x - 2 + y + 4 ).( x - 2 - y - 4 )

D = ( x + y + 2 ).( x - y - 6 )