Question

Expand and simplfy (x+3)(x-3)(3x+2)

Answer 1

`{3x}^(3) + {2x}^(2) - 27x - 18`

Explanation:

1) Use difference of squares: a² - b² = (a + b) (a - b).

`( {x}^(2) - {3}^(2) )(3x + 2)`

2) Simplify 3² to 9.

`( {x}^(2) - 9)(3x + 2)`

3) Use The FOIL method: (a + b) (c + d) = ac + ad + bc + bd.

`{3x}^(3) + {2x}^(2) - 27x - 18`

Therefor, the answer is 3x³ + 2x² + -26x -18.