Answer:
Option B
Step-by-step explanation:
Complex roots occur as conjugate pairs so the third root is -3 - i ( note that the sign changes from + to -).
So in factor form we have:-
(x - 2)(x - (-3 + i))(x - (-3 - i)) = 0 Let's expand the last 2 factors first:-
(x - (-3 + i))(x - (-3 - i))
= (x + 3 - i)(x + 3 + i)
= x^2 + 3x +ix + 3x + 9 + 3i - ix - 3i - i^2
= x^2 + 6x + 9 - (-1)
= x^2 + 6x + 10
Now multiplying by (x - 2):-
(x - 2)(x^2 + 6x + 10) = 0
x^3 + 6x^2 + 10x - 2x^2 - 12x - 20 = 0
x^3 + 4x^2 - 2x - 20 = 0 (answer)
Option B
The value of constant a is -5
Further explanation:
We will use the comparison of co-efficient method for finding the value of a
So,
Given

As it is given that
(x^2 - 3x + 4)(2x^2 +ax + 7) = 2x^4 -11x^3 +30x^2 -41x +28
In this case, co-efficient of variables will be equal, so we can compare the coefficients of x^3, x^2 or x
Comparing coefficient of x^3

So the value of constant a is -5
Keywords: Polynomials, factorization
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Answer: y=4 x=27
Step-by-step explanation: 2y+3=11
-3 -3
2y=8
/2 /2
y=4
2/3x=18
(3) (3)
2x=54
/2 /2
X=27
Vectors and scalars are not the same quantity
Using the z-distribution, it is found that the 90% confidence interval for mean calories in a 30-gram serving of all chocolate chip cookies is (143, 149).
We are given the <em>standard deviation</em> for the population, which is why the <em>z-distribution </em>is used to solve this question.
The information given is:
- Sample mean of
.
- Population standard deviation of
.
- Sample size of
.
The confidence interval is:
The critical value, using a z-distribution calculator, for a <u>95% confidence interval</u> is z = 1.645, hence:


The 90% confidence interval for mean calories in a 30-gram serving of all chocolate chip cookies is (143, 149).
A similar problem is given at brainly.com/question/16807970