1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
eimsori [14]
3 years ago
15

R(x) = -0.21x^3 + x^2 - 8.1x - 3 for x= -1 and x = 2

Mathematics
1 answer:
Minchanka [31]3 years ago
3 0

Answer:

r(-1) = 6.31 and r(2) = -16.88

Step-by-step explanation:

* Lets read the problem and solve it

- Evaluate means find the value, so evaluate r(x) means find the value

 of it at the given values of x

∵ r(x) = -0.21x³ + x² - 8.1x - 3

∵ x = -1 and x = 2

- Then find r(-1) by substitute x by -1 and find r(2) by substitute x by 2

# At x = -1

∴ r(-1) = -0.21(-1)³ + (-1)² - 8.1(-1) - 3  

∴ r(-1) = -0.21(-1) + (1) - 8.1(-1) - 3

∴ r(-1) = 0.21 + 1 + 8.1 - 3

∴ r(-1) = 6.31

# At x = 2

∴ r(2) = -0.21(2)³ + (2)² - 8.1(2) - 3  

∴ r(2) = -0.21(8) + (4) - 8.1(2) - 3

∴ r(2) = -1.68 + 4 - 16.2 - 3

∴ r(2) = -16.88

* r(-1) = 6.31 and r(2) = -16.88

You might be interested in
I need help with this as soon as possible. <br> #7 &amp; 8
Anvisha [2.4K]
If I knew the answer I would helped u b,
7yx
ut I'm only in 7th grade but I will try
4 0
3 years ago
Between which two numbers is Negative two-thirds located on a number line?
klemol [59]

Answer:-1 and 0

Step-by-step explanation:

5 0
4 years ago
On a test, Shane answered 37 out of 40 questions correctly . What portion of his answers was correct
nikitadnepr [17]
37x2= 74
37/2=18.5
74+18.5=92.5
93%
8 0
3 years ago
What is 442.1 × 11 =​
Marta_Voda [28]

Answer: 4,863.1

Step-by-step explanation:

7 0
3 years ago
A cigarette industry spokesperson remarks that current levels of tar are no more than 5 milligrams per cigarette. A reporter doe
d1i1m1o1n [39]

Answer:

t=\frac{5.63-5}{\frac{1.61}{\sqrt{15}}}=1.516  

df=n-1=15-1=14  

Since is a right tailed test the p value would be:  

p_v =P(t_{14}>1.516)=0.076  

If we use a significance level of 0.05 we see that p_v > \alpha and then we can conclude that we don't have evidence in order to conclude that the mean is higher than 5.63, so then the claim makes sense.

Step-by-step explanation:

Data given and notation  

\bar X=5.63 represent the sample mean  

s=1.61 represent the standard deviation for the sample  

n=15 sample size  

\mu_o =15/tex] represent the value that we want to test  &#10;[tex]\alpha 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 to be tested  

We need to conduct a hypothesis in order to determine if the average is more than 5.63, the system of hypothesis would be:  

Null hypothesis:\mu \leq 5.63  

Alternative hypothesis:\mu > 5.63  

Compute the test statistic  

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{s}{\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".  

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

t=\frac{5.63-5}{\frac{1.61}{\sqrt{15}}}=1.516  

Now we need to find the degrees of freedom for the t distribution given by:

df=n-1=15-1=14  

P value

Since is a right tailed test the p value would be:  

p_v =P(t_{14}>1.516)=0.076  

If we use a significance level of 0.05 we see that p_v > \alpha and then we can conclude that we don't have evidence in order to conclude that the mean is higher than 5.63, so then the claim makes sense.

3 0
3 years ago
Other questions:
  • 7-8x+5=-4 ~Solving Equations
    10·1 answer
  • Give the coordinates and quadrant of Point Z
    9·1 answer
  • I’m trying to help my sister. I don’t know what to do.
    5·1 answer
  • In Kim's class 5 times as many students take the bus as those who walk. A total of 24 students walk or take rhe bus. How many mo
    5·1 answer
  • PLEASE HELP ASAP!! will give brainlist :)
    9·1 answer
  • Which statement is true about the extreme value of the given quadratic equation? A. The equation has a maximum value with a y-co
    14·1 answer
  • A toy factory makes 15 teddy bears every 10 minutes. The factory makes teddy bears for 8 hours each work day. What is the fewest
    10·1 answer
  • Solve the equation 4(c-3)-8
    12·1 answer
  • A school counselor heard that teenagers sleep an average of 9 hours per night on the weekend. The counselor
    13·1 answer
  • Which of the following is most likely the next step in the series?<br> Look at the photo
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!