What is the value of -2xy if x = -1 and y= 6? A. 12 B. -12 C. 26 D. 8

Anna is watching a space shuttle launch 6 miles from Cape Canaveral in Florida. When the angle of elevation from her viewpoint t

vichka [17]

Use this calculater operations calculater

5 0

3 years ago

A sequence can be generated by using an=4a(n-1)

WITCHER [35]

This problem is half understanding the question and half just plugging in numbers.

Understanding the Question:
So its saying that n = whole number bigger than one, making n = 2, 3, 4, 5, etc.

Now try plugging any number n into the $a_n = 4a_{n-1}$ equation. Let's use 2 to make it simple. If you plug in 2, you get:
$a_2 = 4a_{2-1}\\
a_2 = 4a_1$
Remember that the subscripts (the small numbers in the corner) are simply the term number. $a_1$ is term 1, $a_2$ is term 2, etc. The equation is saying that "term 2 = 4 times term 1."

If you keep plugging in random numbers for n, you'll see that the equation basically says, "a term = 4 times the term right before it." That makes it easy to plug and chug to get our answer.

Plugging and Chugging
Now we understand the question is asking for the first 4 terms, and each term is 4 times the last term. You're told that term 1, $a_1$ = 6. That makes the next four terms:

Term 2
$a_2 = 4a_{2-1}\\
 a_2 = 4a_1\\
 a_2 = 4(6)\\
 a_2 = 24$

Term 3
$a_3 = 4a_{3-1}\\ a_3 = 4a_2\\ a_3 = 4(24)\\ a_3 = 96$

Term 4
$a_4 = 4a_{4-1}\\ a_4 = 4a_3\\ a_4 = 4(96)\\ a_4 = 384$

Your first 4 terms are 4, 24, 96, and 384.

--------

Answer: A) F

6 0

4 years ago

The volume of a right cylinder is V = πr2h. If we have an oblique cylinder, like in the figure, what is the volume of a cross-se

olchik [2.2K]

Since you did not attach any picture we cannot say for sure what is the correct answer, but we can discuss the options in order to find the most probable correct answer.

First of all, according to the Cavalieri's principle, an oblique cylinder has the same volume as a right cylinder with the same base surface area and same height.
A cross-section of an oblique cylinder will be a small right cylinder with the same base surface area and a height as small as possible.

I guess the oblique cylinder has height h and it is divided into many (probably 10) cross-sections.

Option A: πr2h
This is exactly the volume of the right cylinder, therefore, unless you are given a cross-section of height h (which would be too easy), this won't be the correct answer.

Option B: 4πr2h
This is 4 times the right cylinder. Again, here the height of the cross-section should be 4h, but it doesn't sound like a possible data (too easy again).

Option C: 1 10 πr2h
Here comes a n issue with the notation: I think the right number you meant to write is (1/10)·πr2h and not 110·πr2h.
If I am right, this means that your oblique cylinder of height h is divided into 10 cross-sections, and therefore the volume of each of these cross-sections will be a tenth of the volume of the oblique cylinder, which means 1/10·πr2h.

Option D: 1 2 πr2h
Here, we have the same notation issue as before. I think you meant (1/2)·πr2h.
Here, your oblique cylinder height h should be divided into only 2 cross-sections. Now, we said the cross-section's height should be the smallest as possible, so an oblique cylinder divided only into two pieces doesn't sound good.

Therefore, the most probable correct answer will be C) (1/10)·πr2h

8 0

3 years ago

Read 2 more answers

14 friends go out for dinner and the bill for food and drink comes to £130. The friends decided to add a 5% tip on the top of th

Hitman42 [59]

The amount each friend does pay is £9.75

<h3>How to calculate the pay of each friend using fractions and arithmetic operations?</h3>

We are going to find 5% of the total amount paid and divide it by the numbers of all the friends to determine the amount paid by each one of them.

From the given information: