Nếu câu hỏi là phân tích đa thức thành nhân tử:

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

Phân tích đa thức thành nhân tử

c: \(x^2-4x^2y^2+y^2+2xy\)

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

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

d: \(7x^2-14xy^2+7y^4\)

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

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

Phan h da thuc thanh nhan tu a ban ?

Ta co 

7x²-14xy+7y²

=7(x²-2xy+y²)

=7(x-y)²

Ta có:\(7x^2-14xy+7y^2\)

\(=7\left(x^2-2xy+y^2\right)\)

\(=7\left(x^2-2.x.y+y^2\right)\)

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

a) \(5a\left(x-3y\right)+8\left(3y-x\right)\)

\(=5a\left(x-3y\right)-8\left(x-3y\right)\)

\(=\left(x-3y\right)\left(5a-8\right)\)

b) \(7x^2-14xy+7y^2-7z^2\)

\(=7\left(x^2-2xy+y^2-z^2\right)\)

\(=7\left[\left(x^2-2xy+y^2\right)-z^2\right]\)

\(=7\left[\left(x-y\right)^2-z^2\right]\)

\(=7\left(x-y-z\right)\left(x-y+z\right)\)

a) 5a(x-3y) + 8(3y-x)

= 5a(x-3y) - 8(x-3y)

=(5a-8)(x-3y)

b) 7x²-14xy+7y² -7z²

= 7(x²-2xy+y²-z²)

=7((x-y)² - z²)

=7(x-y-z)(x+y+z)

c) \(\left(x^2-x+6\right)^2+\left(x-3\right)^2\)

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

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

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

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

a) 7x² - 14xy + 7y²

= 7(x² - 2xy + y²)

= 7(x - y)² 

b)  x² + 3x - 10

= - ( x² - 3x + 10 ) 

= - ( x² - 2 . 3/2x + 9/4 + 31/4 ) 

= - (( x - 3/2 )² + 31/4

= (x - 3/2)² - \(\left(\sqrt{\frac{31}{4}}\right)^2\)

=  \(\left(x-\frac{3}{2}-\sqrt{\frac{31}{4}}\right)\left(x-\frac{3}{2}+\sqrt{\frac{31}{4}}\right)\)

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

4x⁴ - 9x²

= 4x² . x² - 9x² 

= (4x² - 9)x²

Ko chắc đâu bạn ak!

\(4x^4-9x^2\)

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

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

25-a²+4ab-4b² 

= 25-(a² -4ab+4b²)=5²-(a-2b)² =(5-a+2b)(5+a-2b)

7x²-14xy²+7y⁴

=7(x²-2xy+y²)=7(x-y)²

X²+4x-y²+4

= (x²+4x+4)-y²=(x+2)²-y²=(x+2-y)(x+2+y)

4x⁴-9x²

=x²(4x²-9)=x²(2x-3)(2x+3)

2x³-8x²+8x =2x(x²-4x+4)=2x(x-2)²

6xy+5x-5y-3x²-3y²

=(-3x²-3y²+6xy)+5(x-y)=-3(x²-2xy+y²)+5(x-y)=-3(x-y)²+5(x-y)=(x-y)(5+3y-3x)

a,   \(7x^2-14xy^2+7y^4=7\left(x^2-2xy^2+y^4\right)=7\left(x-y^2\right)^2\)

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

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

Hiện giờ mình cần câu b nữa nên ai có khả năng để giải giúp mình gì giải giúp nhé ! 

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