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4 years ago

Prove that there exists a unique real number solution to the equation x3 + x2 − 1 = 0 between x = 2/3 and x=1

1 answer:

7 0

Replace each of the x values given to see if they give 0.

0=(2/3)³+(2/3)²-1
0=(8/27)+(4/9)-1
0≠-0.259

0=(1)³+(1)²-1
0≠1

Therefore, you can see that the solution would have to be between 2/3 and 1.

Hope I helped :)

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If s(t) =60/t, to find s(10), substitute 10 in for t, to get 60/10= 6 TRUE OR FALSE

iogann1982 [59]

Answer:

THE ANSWER IS TRUE

Step-by-step explanation:

5 0

3 years ago

Determine if the equation defines y as a function of x: 2xy=1

Leona [35]

Solve for y...

2xy=1

y=1/(2x)

So this is a function as each x value (with the exception of x=0) produces just one value for y. However, technically there is a vertical asymptote about the vertical line x=0. So there is a discontinuity as x=0.

I say this technically, because most would say that this function is true even with the discontinuity (as they do with say y=tana), but technically the discontinuity makes this not a function because another requirement of a function is for their to be an actual output value for each input value. In this case division by zero when x=0 is undefined and cannot be included as part of a function. So if you are picky about being absolute, 2xy=1 is really two functions. One with a domain of (-oo,0) and another with a domain of (0,+oo).

3 0

3 years ago

Suppose that when a transistor of a certain type is subjected to an accelerated life test, the lifetime x (in weeks) has a gamma

elena-14-01-66 [18.8K]

Answer:

a) $P(1 \leq X \leq 40)$

In order to find this probability we can use excel with the following code:

=GAMMA.DIST(40;5,8,TRUE)-GAMMA.DIST(1,5,8,TRUE)

And we got:

$P(1 \leq X \leq 40)=0.560$

b) $P(X \geq 40)=1-P(X$

In order to find this probability we can use excel with the following code:

=1-GAMMA.DIST(40,5,8,TRUE)

And we got:

$P(X \geq 40)=1-P(X$

Step-by-step explanation:

Previous concepts

The Gamma distribution "is a continuous, positive-only, unimodal distribution that encodes the time required for $\alpha$ events to occur in a Poisson process with mean arrival time of $\beta$ "

Solution to the problem

Let X the random variable that represent the lifetime for transistors

For this case we have the mean and the variance given. And we have defined the mean and variance like this:

$\mu = 40 = \alpha \beta$ (1)

$\sigma^2 =320= \alpha \beta^2$ (2)

From this we can solve $\alpha$ and [/tex]\beta[/tex]

From the condition (1) we can solve for $\alpha$ and we got:

$\alpha= \frac{40}{\beta}$ (3)

And if we replace condition (3) into (2) we got:

$320= \frac{40}{\beta} \beta^2 = 40 \beta$

And solving for $\beta = 8$

And now we can use condition (3) to find $\alpha$

$\alpha=\frac{40}{8}=5$

So then we have the parameters for the Gamma distribution. On this case $X \sim Gamma (\alpha= 5, \beta=8)$

Part a

For this case we want this probability:

$P(1 \leq X \leq 40)$

In order to find this probability we can use excel with the following code:

=GAMMA.DIST(40;5,8,TRUE)-GAMMA.DIST(1,5,8,TRUE)

And we got:

$P(1 \leq X \leq 40)=0.560$

Part b

For this case we want this probability:

$P(X \geq 40)=1-P(X$

In order to find this probability we can use excel with the following code:

=1-GAMMA.DIST(40,5,8,TRUE)

And we got:

$P(X \geq 40)=1-P(X$

6 0

3 years ago

Pls help put formula as well ( u don’t have too but if u can pls do ) giving brainliest !

Roman55 [17]

1. 198.56
Step-by-step explanation:
To find the volume of a cylinder, you need to find the area of the cross-section (one of the circles on the side) and multiply it by the length.
Area of the circle = π = π x (5.3/2) x (5.3/2) = π x 2.65 x 2.65 = 7.0225π
Volume of the cylinder = 7.0225π x 9 = 63.2025π = 198.56 2. V
=
a
base
×
h

V
=
π
r
2
×
h

V
=
π
(
d
2
)
2
×
h

V
=
π
(
6.6
2
)
2
×
9.9

V
=
338.7
c
m
3

Hopefully this helps!

7 0

3 years ago

What is the value of the expression below? |6| + |-4|

Afina-wow [57]

Answer:

Your answer is 10

Step-by-step explanation:

The absolute value of |6| = 6

The absolute value of |-4| = 4

6 + 4 = 10, your answer!

Hope this helped :)

4 0

3 years ago

Read 2 more answers