Question

LCM of x²+5x+6 and x²-x-6 is ………………………

Answer 1

Answer:

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

Step-by-step explanation:

Given:

$x^2 + 5x + 6$

$x^2 - x - 6$

Required:

LCM of the polynomials

SOLUTION:

Step 1: Factorise each polynomial

$x^2 + 5x + 6$

$x^2 + 3x + 2x + 6$

$(x^2 + 3x) + (2x + 6)$

$x(x + 3) + 2(x + 3)$

$(x + 2)(x + 3)$

$x^2 - x - 6$

$x^2 - 3x +2x - 6$

$x(x - 3) + 2(x - 3)$

$(x + 2)(x - 3)$

Step 2: find the product of each factor that is common in both polynomials.

We have the following,

$x^2 + 5x + 6 = (x + 2)(x + 3)$

$x^2 - x - 6 = (x + 2)(x - 3)$

The common factors would be: =>

$(x + 2)$ (this is common in both polynomials, so we would take just one of them as a factor.

$(x + 3)$ and,

$(x - 3)$

Their product = $(x - 3)(x + 3)(x +2) = (x^2 - 9)(x + 2)$