Question

f) 𝑥3+27+(𝑥+3)(𝑥−9)

Answer 1

x^3+27+(x+3).(x-9) 

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Answer 2

\(x^3+27+(x+3)(x+9)\)

\(= (x^3+27)+(x+3)(x+9)\)

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

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

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

\(=x(x+3)(x-2)\)

Answer 3

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