Question

if x=-3 is root of f(x)=x3+ax2+11x+6 find a

Answer 1

Answer:

6

Step-by-step explanation:

given :- x + 2 a factor of x³ + ax² + 11x + 6

equating x + 2 with 0

➡ x + 2 = 0

➡ x = -2

we know that remainder is 0 when any polynomial is divided by it's factor.

therefore p(-2) = (-2)³ + a(-2)² + 11(-2) + 6 = 0

➡ -8 + 4a - 22 + 6 = 0

➡ -8 - 22 + 6 + 4a = 0

➡ -24 + 4a = 0

➡ 4a = 24

➡ a = 24/4

➡ a = 6

verification :-

= -24 + 4(6)

= -24 + 24

= 0

hence, the value of a is 6

i hope this help you,and i am kindof new here .        :-)

Answer 2

Answer:

thank you

Step-by-step explanation:

Answer

Open in answr app

x3−6x+11x−6=0

Put X=1

1−6+11−6=0

1 is root of equation, so (x−1) is factor of x3−6x2+11x−6

x2−5x+6=0

(x−3)(x−2)=0

x=2,3

root of cubic equation =1,2,3