From the sum of 3a^2−ab−2b^2 and 2a^2+5ab−3b^2 subtract a^2−3ab−4b^2

A particle moves along the x-axis so that its velocity in feet per second at time x, in seconds, is modeled by the quadratic fun

Katyanochek1 [597]

For this case we have the following equation:

$y = 2x ^ 2 - 10x + 12$

Where, we have the following variables:

x: time in seconds

y: speed in feet per seconds

For the initial velocity, we evaluate x = 0 in the given equation:

$y = 2 (0) ^ 2 - 10 (0) + 12\\y = 12$

Therefore, the initial speed is 12 feet per second.

Answer:

The particle's initially velocity is 12.

6 0

3 years ago

Polymer composite materials have gained popularity because they have high strength to weight ratios and are relatively easy and

Brums [2.3K]

Answer:

$t=\frac{51.6-48}{\frac{1.1}{\sqrt{10}}}=10.349$

$p_v =P(t_9>10.349)=1.34x10^{-6}$

If we compare the p value and the significance level given for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we reject the null hypothesis, and the the actual mean is significantly higher than 48 MPa at 5% of significance.

Step-by-step explanation:

1) Data given and notation

$\bar X=51.6$ represent the sample mean

$s=1.1$ represent the standard deviation for the sample

$n=10$ sample size

$\mu_o =48$ represent the value that we want to test

$\alpha=0.05$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to determine if the mean score is higher than 48, the system of hypothesis would be:

Null hypothesis: $\mu \geq 48$

Alternative hypothesis: $\mu > 48$

We don't know the population deviation, so for this case is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

We can replace in formula (1) the info given like this:

$t=\frac{51.6-48}{\frac{1.1}{\sqrt{10}}}=10.349$

Calculate the P-value

First we find the degrees of freedom:

$df=n-1=10-1=9$

Since is a one-side upper test the p value would be:

$p_v =P(t_9>10.349)=1.34x10^{-6}$

Conclusion

If we compare the p value and the significance level given for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we reject the null hypothesis, and the the actual mean is significantly higher than 48 MPa at 5% of significance.

5 0

3 years ago

Can SOmeone please help me i need to get a good grade on this please!!!!!!

Rudik [331]

Answer:

20 Units

Step-by-step explanation:

Hight times length/by half is tribular prism Formula

3 0

3 years ago

Identify the dependent and independent variables in each situation.

klemol [59]

A. independent (x) - expenses, dependent (y) - total cost
B. independent (x) - area, dependent (y) - price
C. independent (x) - time, dependent (y) - distance
D. independent (x) - size of carton, dependent (y) - number of items

6 0

3 years ago

Read 2 more answers

What are the two solutions of 2x^2 = -X^2 - 5x - 1?

Sidana [21]

Answer:

Step-by-step explanation:

Let's solve 2x^2 = -X^2 - 5x - 1. Consolidate all terms on the left side and write 0 on the right side:

3x^2 + 5x + 1 = 0. This is a quadratic equation. Let's solve it for x using the quadratic formula:

a = 3, b = 5, c = 1, and so the discriminant is b^2 - 4ac = 5^2 - 4(3)(1) = 13. Because the discriminant is positive, we know that there are two distinct, real roots; the graphs of y = 2x^2 and y = x^2 - 5x - 1 intersect in two places whose x-coordinates are the real roots mentioned above.

Answer A is not correct as stated, but would be correct if we were to replace "the y-coordinates" with "the x-coordinates."

Answer C would be correct if and only if we write y = x^2 - 5x - 1.

6 0

4 years ago