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3 years ago

Do anyone know how to do this problem

Mathematics

1 answer:

Nikolay [14]3 years ago

7 0

Answer:

A≈ 50.27

Step-by-step explanation:

A=πr^2

8 divided by 2 to get the radius which is 4

π4^2

π4^2 = 50.27

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Solve the following system of inequalities graphically on the set of axes below. State

tankabanditka [31]

Answer:

The answer is definitely C

Step-by-step explanation:

Following the system of inequalities will graph this solution best on the graph, it is the inequality represented in the graph.

ur wlcm :)

correct me if im wrong

brainliest please?

6 0

3 years ago

Herman horse trader bought a horse for $600 and then sold it for $700. The next day he bought it back for $800 and then sold it

Nimfa-mama [501]

700-600=100. 100-800= -700. -700+900= 300

The horse trader made three hundred dollars

6 0

4 years ago

Find the absolute maximum and absolute minimum values of f on the given interval. f(t) = 2 cos(t) + sin(2t),[0, π/2].

castortr0y [4]

Answer:

The absolute maximum is $\frac{3\sqrt 3}2$ and the absolute minimum value is $0.$

Step-by-step explanation:

Differentiate of $f$ both sides w.r.t. $t$ ,

$f(t)=2 \cos t+\sin 2t$

$\Rightarrow f'(t)=-2\sin t+2\cos 2t$

Now take $f'(t)=0$

$\Rightarrow -2\sin t+2\cos 2t=0$

$\Rightarrow 2\cos 2t=2\sin t$

$\Rightarrow \cos 2t=\sin t$

$\Rightarrow 1-2\sin ^2t =\sin t \quad \quad [\because \cos 2t = 1-2\sin ^2t]$

$\Rightarrow 2\sin ^2t+\sin t-1=0$

$\Rightarrow 2\sin ^2t+2\sin t-\sin t-1=0$

$\Rightarrow 2\sin t(\sin t+1)-1(\sin t+1)=0$

$\Rightarrow (\sin t+1)(2\sin t-1)=0$

$\Rightarrow \sin t+1=0 \;\text{and}\; 2\sin t-1=0$

$\Rightarrow \sin t =-1 \;\text{and}\; \sin t =\frac 12$

In the interval $0\leq t\leq \frac {\pi}2$ , the answer to this problem is $\frac {\pi}6$

Now find the second derivative of $f(t)$ w.r.t. $t$ ,

$f''(t)=-2\cos t-4\sin 2t$

$\Rightarrow \left[f''(t)\right]_{t=\frac {\pi}6}=-2\times \frac {\sqrt 3}2-4\times \frac{\sqrt 3}2=-3\sqrt 3$

Thus, $f(t)$ is maximum at $t=\frac {\pi}6$ and minimum at $t=0$

$\left[f(t)\right]_{t=\frac {\pi}6}=2\times \frac {\sqrt 3}2+\frac{\sqrt 3}2=\frac{3\sqrt 3}2\;\text{and}\;\left[f(t)\right]_{t=\frac{\pi}2}= 2\times 0+0=0$

Hence, the absolute maximum is $\frac{3\sqrt 3}2$ and the absolute minimum value is $0$ .

7 0

3 years ago

A research report describing the results from a repeated-measures t test states that "t(22) = 1.71, p > .05."

Aleonysh [2.5K]

Answer:

b) Fail to reject the null hypothesis with a sample of n = 23 participants

Step-by-step explanation:

Hello!

A "Repeated-measures t-test" is also known as "paired sample t-test" In this type of test you have only one sample and you measure two variables of interest to each experimental unit. Since both study variables are measured in the same units they are said to be dependent.

The most common example of this type of test is the "before-after treatment" experiment.

The degrees of freedom of this experiment are

, so if the test was conducted under a t₂₂ distribution, then the sample size was n= 23 experimental units. Remember if you use the p-value approach, to make a decision over the null hypothesis you have to compare it to the level of significance following the decision rule:

If the p-value ≤ α, you reject the null hypothesis.

If the p-value > α, you do not reject the null hypothesis.

In this example is specified that the p-value is greater than the level of significance, then the decision is to not reject the null hypothesis.

With all this in consideration, the correct option is b)

U hope you have a SUPER day!

6 0

3 years ago

A tree is 7 ft tall when it is planted and this type of tree grows two feet per year. How tall will the tree be in 6 years? How

s344n2d4d5 [400]

2x+7=?

X=6

2(6)+7=

12+7=19

In six years, the tree will be 19ft

2x+7=44

Minus seven on both sides

2x=37

Divide two from both sides

X=18.5

Thus, it will take 18 and a half years for the tree to reach 44ft

4 0

4 years ago

Do anyone know how to do this problem​

Do anyone know how to do this problem