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## #1 Re: Help Me ! » Word problems with integration » 2013-02-28 21:19:32

Thanks bob bundy!

In Q1,using integration, I got the same answer as when I plugged in the values in the position function you gave but could you still
check my solution for any flaw?
Here it is:
v(t)=-10t+C*
s(t)=-5t²+C*t+C**

Given that speed=10 and since speed=absolute value of velocity, v=-10
v(0)=-10t+C*=-10
C*=-10

s(t)=-5t²-10t+C**
but s(3)=0
C**=75
s(t)=-5t²-10t+75

s(0)-s(3)=75

## #2 Help Me ! » Word problems with integration » 2013-02-28 04:52:48

295Ja
Replies: 3

Problem 1:
A ball was thrown downward from the top of a building at a speed of 10 meters per
second and it hit the ground 3 seconds later. How tall was the building? [Note: Use
-10 m/s² for acceleration due to gravity.]

>>Here's what I think I should do:
1. Find the velocity then position functions
Here's what I got:
Velocity Function:
v(t)=-10t+C*
Position Function:
s(t)=-5t²+C*t+C**
[Note: C*=constant after integrating a(t) and C**= constant after integrating v(t)]
2.Find the value of C* and C**
My question: is it right to use these: v(3)=0 and s(3)=0 to find them?
3.Evaluate s(0)-s(3)

Problem 2
The base of a solid S is the region bounded by y =square root of (16-x²) and the x-axis, and each
cross-section perpendicular to the x-axis is an isosceles right triangle having one leg on
the base of S. Using the method of slicing, determine the volume of S.

>>I have a hard time with this problem. A help on visualizing the figure and/or setting-up the integral that will give the volume would do.

Thank you!

## #3 Help Me ! » Non-borel » 2013-02-12 19:27:58

295Ja
Replies: 0

Hi!
Could you give me a subset of the Real line which is not in Borel but is in the power set to prove that Borel field is not the power set of R?

## #4 Re: Help Me ! » Limit » 2012-11-20 10:18:37

Hi stefy! Just want to say thanks!

## #5 Re: Help Me ! » Limit » 2012-11-20 05:12:44

Hi!
I tried to read about the L'Hopital's rule but I found out that for me to use that rule, I need to learn to evaluate derivatives.I must agree that the with the use of the rule, the solution would be simpler but may I ask for a solution  without using that rule? It is because we are not yet on derivatives and I think  the purpose of the problem, being included in the practice exercises of the topic that introduces limits, is for us to be able to master the basic theorems about limits that we had just learned.

## #6 Re: Help Me ! » Limit » 2012-11-20 04:41:08

Not yet. We had just started studying limits. Do I need to learn that rule first to solve the problem I posted?

## #7 Help Me ! » Limit » 2012-11-20 04:23:32

295Ja
Replies: 7

Hi! Please, help me with this one:

Evaluate the limit of (3-x)/(3-(sqrt of (6x-x²)) as x approaches 3 from the left.

What I did was this: I substitute 3 and found out that what I have is an indeterminate form of type 0/0. I then tried rationalizing the denominator but after it, I still arrived at the the same indeterminate form.

If what I did was right, please let me know the next step to solve the problem. If not, I'd like to ask for the right solution. I'll be waiting for replies then. Thanks in advance!

## #8 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-15 11:41:03

Thanks everyone! You guys are so cool!

## #9 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-14 23:15:50

Hello anonimnystefy! It's been a long time! I just want to keep my promise to you...
I just got the result of my exam earlier this day.
I didn't got the perfect score due to carelessness but anyway, I still passed. Better luck next time, I guess.

Have a great day!

## #10 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-03 01:05:31

Thanks! I'll let you know.

## #11 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-03 00:42:49

Oh, I see. I'll know the result on Monday, maybe. But I think the exam that I took earlier is a little bit simplier than I expected, fortunately.

## #12 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-03 00:15:58

Hi anonimnystefy!

We had a long exam in math.
How about you? Do you still have classes later?

## #13 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-02 23:49:23

Thank you noelevans

## #14 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-02 13:47:15

Whooh! Seems like you're an avid reader of mangas.
I'll tell my brother about the Death note's manga.
I'm sorry cause I'm about to log-out now. Its because I'm going to prepare for my class later. It's been nice knowing more of you!
Bye-bye for now and until next time!

## #15 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-02 13:29:36

Same here. I think I'm only one of the few teens who is not yet that hooked in mangas and animes.But last week, I watched Princess Mononoke and I liked it. I have a brother who really love anime. I have heard him telling how good Death Note is. He also liked Fairy Tail and Reborn.

## #16 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-02 13:12:10

I have read and watched only few. I have watched Naruto for a few times and I don't know that much about it. By the way,Naruto is one of the favorite animes that boys watch here.

## #17 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-02 13:04:36

Yes. I have lot of friends who love to read mangas. By the way, are you refering manga as a comic book or animated film?

## #18 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-02 12:53:47

anonimnystefy I'm not sure if my avatar is a manga character.

I hope so!:D

## #20 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-02 06:01:40

Thank you again! I guess I'll be thanking you guys a lot of times more in the near future.

## #21 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-02 05:55:42

Thank you bob bundy,bobbym and anonimnystefy!

Ok. Thank you!

## #23 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-02 05:16:11

anonimnystefy: that's exactly what I want. Thank you!

## #24 Re: Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-02 05:10:35

x/is part of:
/8-x/ (absolute value of 8-x)

then 2 is added to /8-x/

## #25 Help Me ! » Inequality having Absolute Value and Constant on its 2 side » 2012-08-02 05:05:08

295Ja
Replies: 51

Hello everyone!Please give me ideas on how should I solve problems like this one:

3/8-x/+2<7-2/x-8/

Thanks