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a) x4 + x2 - 27x - 9
= (x4 - 27x) + x2 - 9
= x(x3 - 27) + (x - 3)(x + 3)
= x(x - 3)(x2 + 3x + 9) + (x - 3)(x + 3)
= (x - 3)(x3 + 3x2 + 9x + x + 3)
= (x - 3)(x3 + 3x2 + 10x + 3)
b) x2 - xy - x + y
= x(x - y) - (x - y)
= (x - 1)(x - y)
c) xy + 4 - x2 + 2y
= (xy + 2y) - (x2 - 4)
= y(x + 2) - (x - 2)(x + 2)
= (x + 2)(y - x + 2)
d) xy + y - 2(x + 1)
= y(x + 1) - 2(x + 1)
= (y - 2)(x + 1)
a, x^2 - x - y^2 - y
= (x^2 - y^2) - ( x+ y)
= ( x- y)(x+y) - ( x+y )
= ( x - y - 1 )(x+ y)
b, x^2+ 6x + 9 - y^2
= ( x+ 3)^2 - y^2
= ( x+ 3 -y)( x + 3 +y)
\(a)\)
\(4x^2-y^2+2x+y\)
\(=\left(4x^2-y^2\right)+\left(2x+y\right)\)
\(=\left(2x-y\right)\left(2x+y\right)+\left(2x+y\right)\)
\(=\left(2x+y\right)\left(2x-y+1\right)\)
\(b)\)
\(x^3+2x^2-6x-27\)
\(=x^3+5x^2+9x-3x^2-15x-27\)
\(=x\left(x^2+5x+9\right)-3\left(x^2+5x-9\right)\)
\(=\left(x-3\right)\left(x^2+5-9\right)\)
\(c)\)
\(12x^3+4x^2-27x-9\)
\(=\left(12x^3+4x^2\right)-\left(27x+9\right)\)
\(=4x^2\left(3x+1\right)-9\left(3x+1\right)\)
\(=\left(3x+1\right)\left(4x^2-9\right)\)
\(=\left(3x+1\right)[\left(2x\right)^2-3^2]\)
\(=\left(3x+1\right)\left(2x-3\right)\left(2x+3\right)\)
\(d)\)
\(16x^2+4x-y^2+y^2\)
\(=16x^2+4x\)
\(4x\left(4x+1\right)\)
a) \(x^3+6x^2+12x+8\)
\(=\left(x+2\right)^3\)
b) \(x^3-3x^2+3x-1\)
\(=\left(x-1\right)^3\)
c) \(1-9x+27x^2-27x^3\)
\(=-\left(27x^3-27x^2+9x-1\right)\)
\(=-\left(3x-1\right)^3\)
\(x^2-y^2+4x+4\)
\(=\left(x+2\right)^2-y^2\)
\(=\left(x+2+y\right)\left(x+2-y\right)\)
\(4x^2-y^2+8\left(y-2\right)\)
\(=4x^2-\left(y^2-8y+16\right)\)
\(=4x^2-\left(y-4\right)^2\)
\(=\left(2x+y-4\right)\left(2x-y+4\right)\)
a. x4 - 27x = x ( x3 - 33 ) = = x ( x - 3 ) ( x2 + 3x + 32 ) = x ( x - 3 ) ( x2 + 3x + 9 )
b. x3 + 2x2 + 2x + 1 = ( x3 + 13 ) + ( 2x2 + 2x ) = ( x + 1 ) ( x2 - x + 1 ) + 2x ( x + 1 ) = ( x + 1 ) ( x2 + x + 1 )
c. 4x - 4y + x2 - 2xy + y2 = 4 ( x - y ) + ( x - y )2 = ( x - y ) ( x - y + 4 )
a
\(x^4-27x\)
\(=x\left(x^3-27\right)\)
\(=x\left(x^3-3^3\right)\)
\(=x\left(x-3\right)\left(x^2+3x+9\right)\)
b
\(x^3+2x^2+2x+1\)
\(=x^3+x^2+x^2+x+x+1\)
\(=x^2\left(x+1\right)+x\left(x+1\right)+1\left(x+1\right)\)
\(=\left(x+1\right)\left(x^2+x+1\right)\)
c
\(4x-4y+x^2-2xy+y^2\)
\(=4\left(x-y\right)+\left(x-y\right)^2\)
\(=\left(x-y\right)\left(x-y+4\right)\)
\(x^2-y^2-6x+9=\left(x-3\right)^2-y^2=\left(x-3-y\right)\left(x+3+y\right)\)
\(x^4-27x=x\left(x^3-27\right)=x\left(x-3\right)\left(x^2+3x+9\right)\)
a,x2 - y2 - 6x + 9
( x2 - 6x + 9 ) - y2
( x2 - 2x.3 + 32 ) - y2
( x + 3)2 - y2
[ x + 3 + y ] . [ x + 3 - y ]
b, x4 - 27x = x. ( x3- 27 ) = x . ( x3- 33) = x . ( x - 3 ) . ( x2 + 3x + 9 )
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