Question

Which of the following is not a zero of the polynomial p(x)=x^3+11x^2+36x+36
a) -3
b)-2
c) -6
d)2

Answer 1

$\huge\bf\underline{Solution:-}$

Given :-

• p(x) = x³ +11x² +36x+36

Putting x = -3

$\small:\implies\rm\:( - 3) {}^{3} + 11 \times { - 3}^{2} + 36 \times (-3) + 36 \\ :\implies\rm\: - 27 + 11 \times 9 - 108 + 36 \\ :\implies\rm\: - 135 + 99 + 36 \\ :\implies\rm\: - 135 + 135 \\ :\implies\rm\:0 = 0$

Since we get 0

so, -3 is a zero of given polynomial.

Now putting x = -2

$\small:\implies\rm\: { - 2}^{3} + 11 \times { - 2}^{2} + 36 \times ( - 2) + 36 \\ :\implies\rm\: - 8 + 44 - 72 + 36 \\ :\implies\rm\: - 80 + 80 \\ :\implies\rm\:0 = 0$

So we get 0

so -2 is a zero of given polynomial.

putting x = -6

$\small:\implies\rm\: { - 6}^{3} + 11 \times { - 6}^{2} + 36 \times ( - 6) + 36 \\ \small:\implies\rm\: - 216 + 396 - 216 + 36 \\ \small:\implies\rm\: - 432 + 432 \\ \small:\implies\rm\:0 = 0$

so, we get 0 , so -6 is a zero of given polynomial.

Putting x = 2

$\small:\implies\rm\: {2}^{3} + 11 \times {2}^{2} + 36 \times 2 + 36 \\ \small:\implies\rm\:8 + 44 + 72 + 36 \\ \small:\implies\rm\:162 \neq 0$

So, we didn't get 0

So, 2 is not a zero of given polynomial

Then,

option d is correct.

Answer 2

QUESTION :

Which of the following is not a zero of the polynomial p(x)=x^3+11x^2+36x+36

a) -3

b)-2

c) -6

d)2

ANSWER :

Option d)2 is the answer.

please refer to given attachment for explanation.