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2 years ago

What are the solutions of the equation x6 – 9x3 + 8 = 0? Use u substitution to solve.

1 answer:

4 0

X6 – 9x3 + 8 = 0
let u = x^3
u^2 - 9u + 8 = 0
(u-8)(u-1) = 0
u = 1,8
back substitute
1 = x^3
8 = x^3

x = 1 , 2

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What the the opposite of - 4.1 ?

sdas [7]

The opposite of -4.1 would be 4.1

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2 years ago

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Suppose that Y has density function

zvonat [6]

I'm assuming

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P(Y ≤ 0.4 | Y ≤ 0.8) = P(Y ≤ 0.4 and Y ≤ 0.8) / P(Y ≤ 0.8)

P(Y ≤ 0.4 | Y ≤ 0.8) = P(Y ≤ 0.4) / P(Y ≤ 0.8)

It makes sense to derive the cumulative distribution function (CDF) for the rest of the problem, since F(y) = P(Y ≤ y).

We have

$\displaystyle F(y)=\int_{-\infty}^y f(t)\,\mathrm dt=\int_0^y6t(1-t)\,\mathrm dt=\begin{cases}0&\text{for }y$

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P(Y ≤ 0.4 | Y ≤ 0.8) = 0.352 / 0.896 ≈ 0.393

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P(Y ≤ φ) = 0.95

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which reduces to the cubic

3φ² - 2φ³ = 0.95

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2 years ago

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maw [93]

Base on the question that said to write the letter of the statement or the reason in the said numbers in the question, and in my further analysis and research, the following are the answers:
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Reasons:
#1 R. Given
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2 years ago

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Step-by-step explanation:

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