Question

Check whether x + 2 is a factor of x3 + 2x + 12​

Answer 1

Answer:

no

Explanation:

x+2= -2

3*(-2) + 2*(-2) +12

-6-4+12

-10+12

2

no it is not a factor

Answer 2

$\bf \Large \hookrightarrow \: x \: + \: 2 \: = \: 0$

$\bf \Large \hookrightarrow \: x \: = \: \: - 2$

Put -2 in the equation x³ + 2x + 12 to check the factor.

$\bf \large \rightarrow \: ( - 2) ^{3} \: + \: 2 \: \times \: ( - 2) \: + \: 12$

$\bf \large \rightarrow \: \: - 8 \: - 4 \: \: + \: 12$

$\bf \large \rightarrow \: \: - 12 \: + \: 12$

$\bf \large \rightarrow \:0$

Yes , x + 2 is a factor of x³ + 2x + 12.