a) \(x^4-8x\)
\(=x\left(x^3-8\right)\)
\(=x\left(x-2\right)\left(x^2+2x+4\right)\)
b) \(x^2-5x+10y-4y^2\)
\(=\left(x^2-4y^2\right)-\left(5x-10y\right)\)
\(=\left(x-2y\right)\left(x+2y\right)-5\left(x-2y\right)\)
\(=\left(x-2y\right)\left(x+2y-5\right)\)
c) \(9y^2-4x^2+4x-1\)
\(=9y^2-\left(4x^2-4x+1\right)\)
\(=\left(3y\right)^2-\left(2x-1\right)^2\)
\(=\left(3y-2x+1\right)\left(3y+2x-1\right)\)
a) x4 - 8x
=x(x3-8)
=x(x-2)(x2+2x+4)
b) x2 - 5x + 10y - 4y2
=(x2-4y2)-(5x-10y)
=(x-2y)(x+2y)-5(x-2y)
=(x-2y)(x+2y-5)
c) 9y2 - 4x2 + 4x - 1
=9y2-(4x2-4x+1)
=9y2-(2x+1)2
=[3y-(2x+1)][3y+(2x+1)]
=(3y-2x-1)(3y+2x+1)
