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2 years ago

Which of the following is a polynomial with roots 4, 2i, and −2i?

Mathematics

2 answers:

ivolga24 [154]2 years ago

3 0

Hello,

(x+2i)(x-2i)(x-4)=(x²+4)(x-4)=x^3-4x²+4x-16

Answer C

maks197457 [2]2 years ago

3 0

X = 4; x = 2i; x = -2i

$f(x) = (x - 4)(x - 2i)[x - (-2i)] = (x - 4)\underbrace{(x-2i)(x+2i)}_{a^2-b^2=(a-b)(a+b)}\\\\=(x-4)[x^2-(2i)^2]=(x-4)(x^2-2^2i^2)=(x-4)[x^2-4(-1)]\\\\=(x-4)(x^2+4)=(x)(x^2)+(x)(4)-(4)(x^2)-(4)(4)\\\\=x^3+4x-4x^2-16=\boxed{x^3-4x^2+4x-16}$

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Rectangle ABCD with coordinates A(1,1), B(4,1), C(4,2) and D(1,2) dilates with respect to the origin to give rectangle A’B’C’D’.

Delvig [45]

Answer: Option C.

Step-by-step explanation:

You need to find the distance AB with the formula for calculate the distance between two points:

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2 years ago

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mina [271]

Given

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Explanation:

It is given that,

A single die is rolled.

Then, the sample space is,

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Then,

$\begin{gathered} A=\lbrace1,3,5\rbrace \\ n(A)=3 \end{gathered}$

Let B be the event of getting a number less than 6.

Then,

$\begin{gathered} B=\lbrace1,2,3,4,5\rbrace \\ n(B)=5 \end{gathered}$

Also,

$\begin{gathered} A\cap B=\lbrace1,3,5\rbrace \\ n(A\cap B)=3 \end{gathered}$

Therefore,

$\begin{gathered} P(A\cup B)=P(A)+P(B)-P(A\cap B) \\ =\frac{n(A)}{n(S)}+\frac{n(B)}{n(S)}-\frac{n(A\cap B)}{n(S)} \\ =\frac{3}{6}+\frac{5}{6}-\frac{3}{6} \\ =\frac{3+5-3}{6} \\ =\frac{5}{6} \end{gathered}$

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Answer:

Step-by-step explanation:

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Answer:

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Step-by-step explanation:

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