Question

Thực hiện phép tính

(x-2)(x^2+2x+4)-(x-1)^3+7

x(x+2)(2-x)+(x+3)(x^2-3x+9)

Answer 1

\(\left(x-2\right)\left(x^2+2x+4\right)-\left(x-1\right)^3+7\)

\(=x^3-8-\left(x^3-3x^2+3x-1\right)+7\)

\(=x^3-8+7-x^3+3x^2-3x+1\)

\(=\left(x^3-x^3\right)+\left(7+1-8\right)+3x^2-3x\)

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

Answer 2

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

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

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

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

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

\(=4x+9\)

Answer 3

( x - 2 )( x² + 2x + 4 ) - ( x - 1 )³ + 7

= x³ - 8 - ( x³ - 3x² + 3x - 1 ) + 7 

= x³ - 8 - x³ + 3x² - 3x + 1 + 7

= 3x² - 3x = 3x( x - 1 )

x( x + 2 )( 2 - x ) + ( x + 3 )( x² - 3x + 9 )

= ( x² + 2x )( 2 - x ) + x³ + 27

= 2x² - x³ + 4x - 2x² + x³ + 27

= 4x + 27 

Answer 4

(x-2)(x²+2x+4)-(x-1)³+7

=x³-2³-(x³-3x².1+3x.1²-1³)+7

=x³-8-(x³-3x².+3x.-1)+7

=x³-8-(x³-3x².+3x-1)+7

=x³-8-x³+3x²-3x+1+7

=3x²-3x

=3x.x-3x.1

=3x(x-1)

Answer 5

a, \(\left(x-2\right)\left(x^2+2x+4\right)-\left(x-1\right)^3+7\)

\(=x^3-8-x^3+3x^2-3x+1+7=3x^2-3x\)

b, \(x\left(x+2\right)\left(2-x\right)+\left(x+3\right)\left(x^2-3x+9\right)\)

\(=2x^2-x^3+4x-2x^2+x^3+27=4x+27\)