\(-25x^2\sqrt{2}+10x+4\sqrt{2}=-\sqrt{2}\left(25x^2-\dfrac{10}{\sqrt{2}}-4\right)=-\sqrt{2}.\left(\left(25x\right)^2-2.5.\dfrac{1}{\sqrt{2}}+\dfrac{1}{2}-\dfrac{5}{2}\right)=-\sqrt{2}\left[\left(5x-\dfrac{1}{\sqrt{2}}\right)^2-\dfrac{5}{2}\right]=-\sqrt{2}.\left(5x-\dfrac{1}{\sqrt{2}}-\dfrac{\sqrt{5}}{\sqrt{2}}\right).\left(5x-\dfrac{1}{\sqrt{2}}+\dfrac{\sqrt{5}}{\sqrt{2}}\right)=-\sqrt{2}.\left(5x-\dfrac{1+\sqrt{5}}{\sqrt{2}}\right)\left(5x-\dfrac{1-\sqrt{5}}{\sqrt{2}}\right)\)

\(25x^2-4y^2-4y-1\)

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

25x² - 4y² - 4y - 1

= 25x² - (4y² + 4y + 1)

= (5x)² - (2y + 1)²

= [5x - (2y + 1)][5x + (2y + 1)]

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

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

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

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

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

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

\(25x^2-30x+9=\left(5x-3\right)^2\)

Answer:

\(25x^2-10x+4y-4y^2\)

\(=25x^2-10x+1-4x^2+4y-1\)

\(=\left(25x^2-10x+1\right)-\left(4y^2-2y+1\right)\)

\(=[\left(5x\right)^2-2.5x.1+1]-[\left(2y\right)^2-2.2y.1+1]\)

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

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

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

\(x^3-10x^2+25x-16xy^2\)

\(=x\left(x^2-10x+25-16y^2\right)\)

\(=x\left[\left(x-5\right)^2-16y^2\right]\)

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

p/s: chúc bạn học tốt

A=12x²-16x-9x+12

A=4x(3x-4)-3(3x-4)

A=(3x-4)(4x-3)

dễ mà, tick nha

\(25x^2-4y^2-4y-1=25x^2-\left(2y+1\right)^2\)

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

Trả lời:

1, 25x² - 4y² - 4y - 1

= 25x² - ( 4y² + 4y + 1 )

= ( 5x )² - ( 2y + 1 )²

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