a) \(2x^2+2b^2=x^2+b^2+x^2+b^2=x^2+2xb+b^2+x^2-2xb+b^2=\left(x+b\right)^2+\left(x-b\right)^2\)

=(3x-1)^2+(2y-2)^2-5

= ( 3x-1 )^2+(2y-2)^2-5

\(9x^2-6x+1=\left(3x-1\right)^2\)

C₁: 9x² - 6x + 1 

= (3x)² - 3x.2.1 + 1²

= (3x - 1)²

C₂: 9x² - 6x + 1

= 9x² - 3x - 3x + 1 

= 3x(3x - 1) - (3x - 1) 

= (3x - 1)(3x - 1)

= (3x - 1)²

Bình phương tổng có CT: (a + b)² đấy

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

\(=x^2+2\left(x^2+2x+1\right)+3\left(x^2-4x+4\right)+4\left(x^2+6x+9\right)\)

\(=x^2+2x^2+4x+2+3x^2-12x+12+4x^2+24x+36\)

\(=10x^2+16x+50\)

a, \(25x^2+5xy+\frac{1}{4}y^2=\left(5x\right)^2+2.5x.\frac{1}{2}y+\left(\frac{1}{2}y\right)^2\)

\(=\left(5x+\frac{1}{2}y\right)^2\)

b, \(9x^2+12x+4=\left(3x\right)^2+2.3x.2+2^2=\left(3x+2\right)^2\)

c, \(x^2-6x+5-y^2-4y=\left(x^2-6x+9\right)-\left(y^2+4y+4\right)\)

\(=\left(x-3\right)^2-\left(y+2\right)^2=\left(x-y-5\right)\left(x+y-1\right)\)

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

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

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

Có cái cc

a/ 9x²-12xy+4y² = (3x - 2y)²

b/ 25x²-10x+1 = (5x - 1)²

c/ 9x²-12x+4 = (3x - 2)²

d/ 4x²+20x+25 = (2x + 5)²

e/ x⁴-4x²+4 = (x² - 2)²

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

b/\(\left(5x-1\right)^2\)

c/\(\left(3x-2\right)^2\)

d/\(\left(2x+5\right)^2\)

e/\(\left(x-2\right)^2\)

để thằng này làm cho :

a/\(\left(3x\right)^2-12xy+\left(2y\right)^2\)

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

B/làm cx tương tự 

mấy câu kia cx z