a)  \(x^2+10x+25+y^2+1+2y=\left(x+5\right)^2+\left(y+1\right)^2\)

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

c)  \(x^2-6x+13+y^2+4y=\left(x-3\right)^2+\left(y+2\right)^2\)

d) \(4x^2+2y^2-4xy-2y+1=\left(2x-y\right)^2+\left(y-1\right)^2\)

a. x² + 6x + 9 = (x + 3)²

b. 25 + 10x + x² = (5 + x)²

c. x² + 8x + 16 = (x + 4)²

d. x² + 14x + 49 = (x + 7)²

e. 4x² + 12x + 9 = (2x + 3)²

f. 9x² + 12x + 4 = (3x + 2)²

h. 16x² + 8 + 1 = (4x + 1)²

i. 4x² + 12xy + 9y² = (2x + 3y)²

k. 25x² + 20xy + 4y² = (5x + 2y)²

a) \(=\left(x+3\right)^2\)

b) \(=\left(x+5\right)^2\)

c) \(=\left(x+4\right)^2\)

d) \(=\left(x+7\right)^2\)

e) \(=\left(2x+3\right)^2\)

f) \(=\left(3x+2\right)^2\)

h) \(=\left(4x+1\right)^2\)

i) \(=\left(2x+3y\right)^2\)

k) \(=\left(5x+2y\right)^2\)

a) t² - 8t + x² - 4x + 20 = ( t² - 8t + 16 ) + ( x² - 4x + 4 ) = ( t - 4 )² + ( x - 2 )²

b) 49t² + y² - 10y + 14t + 26 = ( 49t² + 14t + 1 ) + ( y² - 10y + 25 ) = ( 7t + 1 )² + ( y - 5 )²

c) 2x² + 4y² - 2x + 4xy + 1 = ( x² - 2x + 1 ) + ( x² + 4xy + 4y² ) = ( x - 1 )² + ( x + 2y )² ( thay 2 thành 1 vì 2 khó làm lắm:v )

Câu 1:

a, (x-1).(x²-x+1)

b, (2a+b).(2a-b)

Câu 2:

a,(2x-1).(x²-5x+3)

b,(-x²+4x-1).(-x+4)

c,(-2x-3).(x+4)+(-x+1)

d,(-3).(x+4).(x-7)+2.(x-5).(x+1)

Câu 3:

a,5x²-(2x+1).(x-2)-x.(3x+3)+7

b,(5x-2).(x+1)-(x-3).5x+1-17.(x-2)

Giup mình với 

Mình gửi kiểu kia ko được

\(a,=\left(x-4\right)^2\\ b,=\left(\dfrac{1}{2}xy^2+1\right)^2\)

A

A

bình phương tổng chứ

b, B= x^2+ 2xy+y^2 +4y+4

= x^2+2xy+y^2+y^2+4y+4

=(x+y)^2+(y+2)^2

c, C= 2x^2+6xy+9y^2+2x+1

= x^2+6xy+9y^2+x^2+2x+1

= (x+3)^2+(x+1)^2

d, D= x(x+2) +(x+1)(x+3) +2

= x^2+2x+x^2+3x+x+3+2

= x^2+2x+1+x^2+4x+4

= (x+1)^2+(x+2)^2

e, E= x^2-2xy+2y^2+2y+1

= x^2-2xy+y^2+y^2+2y+1

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

f, F= 4x^2-12xy+10y^2+4y+4

=4x^2-12xy+9y^2+y^2+4y+4

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

g, G=2x^2+4xy+4y^2+4x+4

=x^2+4xy+4y^2+x^2+4x+4

=(x+2y)^2+(x+2)^2

Xong r.... dài quá...mới hè lớp 7 nên có j bỏ qua ak