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4 years ago

If f(x) = x^3 – 2x^2, which expression is equivalent to f(i)?

Mathematics

2 answers:

Brums [2.3K]4 years ago

7 0

F(x) = x³ - 2x².

f(i) = i³ - 2i².

i = √-1.

i³ = (√-1)³ = √-1 * √-1 *√-1 = -1*√-1 = -√-1 = -i

i² = (√-1)² = √-1 * √-1 = -1

f(i) = i³ - 2i² = -i - 2(-1) = -i + 2

f(i) = 2 - i

arsen [322]4 years ago

6 0

I=√-1 and all the steps are there

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Step-by-step explanation:

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3 years ago

Sin tita= 0.6892.find the value Of tita correct to two decimal places<br><br>

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Answer:

$\theta \approx 6.28n + 2.38, \quad n \in \mathbb{Z}$

$\theta \approx 6.28n + 0.76, \quad n \in \mathbb{Z}$

Considering $\theta \in (0, 2\pi]$

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Step-by-step explanation:

$\sin(\theta)=0.6892$

We have:

$\sin (x)=a \Longrightarrow x=\arcsin (a)+2\pi n \text{ or } x=\pi -\arcsin (a)+2\pi n \text{ as } n\in \mathbb{Z}$

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$\theta= \arcsin (0.6892)+2\pi n, \quad n \in \mathbb{Z}$

$\theta = \pi -\arcsin (0.6892)+2\pi n, \quad n\in \mathbb{Z}$

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$\theta \approx 6.28n + 2.38, \quad n \in \mathbb{Z}$

$\theta \approx 6.28n + 0.76, \quad n \in \mathbb{Z}$

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3 years ago

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3 years ago

2x² - 5x+1 has roots alpha and beta. Find alpha⁴+beta⁴ without solving the equation.

shepuryov [24]

Answer:

Step-by-step explanation:

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$= \dfrac{625}{16}- \dfrac{168}{16}-\dfrac{24}{16}\\\\\\= \dfrac{433}{16}$

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