Question

If (−2) is a zero of the polynomial P(x)=x^3+ax^2-4x-12 , then find the value of a

easy !!!

Answer 1

Answer:

a = 3

Step-by-step explanation:

(-2)³+a(-2)²-4(-2)-12

-8+4a+8-12

4a-12 = 0

4a = 12

a = 12/4

a = 3

Answer 2

$\huge { \red{ \boxed{ \green { \boxed{ \color{yellow}{ \boxed{ \color{silver}{ \boxed{ \pink { \boxed{ \color{skyblue}{ \boxed{ \fcolorbox{maroon}{purple}{ \bf \blue{a = 3}}}}}}}}}}}}}}}$

Step-by-step explanation:

QUESTION :-

If (-2) is a zero of the polynomial p(x) = x³ + ax² - 4x - 12, then find the value of 'a'.

______________________

SOLUTION :-

If (-2) is a zero of p(x), then p(-2) = 0.

So,

$\bf {( - 2)}^{3} + a {( - 2)}^{2} - 4( - 2) - 12 = 0 \\ \\ \bf = > \cancel{ - 8 }+ a(4) + \cancel{ 8} - 12 = 0 \\ \\ \bf = > 4a - 12 = 0 \\ \\ \bf = > 4a = 12 \\ \\ \bf = > a = \frac{ \cancel {12}^{ \: 3} }{4} \\ \\ = > \bf \purple{a = 3}$

Hence the value of 'a' is 3.

hope it helps.

#BeBrainly :-)