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## #2 Help Me ! » Ap Bc Calc » 2008-01-12 14:17:24

tonyz1949
Replies: 7

[img] C:\Documents and Settings\Antony\My Documents\My Scans\2008-01 (Jan)\scan.jpg

## #3 Help Me ! » AP BC Calculus » 2008-01-12 14:13:34

tonyz1949
Replies: 2

Please look at image and help me solve all the problems.

I am preparing for an exam.

Thank you sooo much.

## #4 Re: Help Me ! » Derivatives » 2008-01-12 14:06:18

Thanks in advance for helping me out. I have an exam. Pleez help me

## #5 Help Me ! » Derivatives » 2008-01-12 14:05:04

tonyz1949
Replies: 3

Let g(x) = f(x² + 1)    Find

a)  g'(x)

b)  g'(2)

c)  g'(x³)

d)  d/dx [g(x³)]

## #6 Help Me ! » Curves » 2008-01-12 13:49:38

tonyz1949
Replies: 1

1. Find the values of a and b such that the function g(x) is continuous everywhere. Justify your answer.

g(x) = 3ax - 2bx² + 1 if x > 2
2ax - 3            if x = 2
4ax³ - 5b         if x < 2

2. Consider the curve given by the equation -4y³ + 3xy = -2x -14
a) Find dy/dx
b) Write an equation for the line tangent to the curve at the point where y = 1

3. Find dy/dx

a) y = 4(3x+5)cos²x

b) y = (2x+1)^(sinx)

Thanks in advance for helping me

## #7 Help Me ! » Physics math » 2007-09-02 12:48:35

tonyz1949
Replies: 4

1) An average family of four uses roughly 1200 liters (about 300 gallons) of water per day. (One liter = 1000 cm^3.) How much depth would a lake lose per year if it uniformly covered an area of 50 square kilometers and supplied a local town with a population of 40,000 people? Consider only population uses, and neglect evaporation and so on.

2) A heavy rainstorm dumps 1.0 cm of rain on a city 5 km wide and 8 km long in a 2-h period. How many metric tons (1 metric ton = 10^3 kg) of water fell on the city? [1 cm^3 of water has a mass of 1 gram = 10^-3 kg.] How many gallons of water was this?

3) Estimate how many days it would take to walk around the world, assuming 10 h walking per day at 4 km/h.

4) If you began walking along one of Earths lines of longitude and walked until you had changed latitude by 1 minute of arc (there are 60 minutes per degree), how far would you have walked (in miles)? This distance is called a nautical mile.

5) How big is a ton? That is, what is the volume of something that weighs a ton? To be specific, estimate the diameter of a 1-ton rock, but first make a wild guess: will it be 1 ft across, 3 ft, or the size of a car? [Hint: Rock has mass per volume about 3 times that of water, which is 1 kg per liter (10^3 cm^3) or 62 lb per cubic foot.]

6) Noahs ark was ordered to be 300 cubits long, 50 cubits wide, and 30 cubits high. The cubit was a unit of measure equal to the length of a human forearm, elbow to the tip of the longest finger. Express the dimensions of Noahs ark in meters, and estimate its volume (m^3).

7) One liter (1000 cm^3) of oil is spilled onto a smooth lake. If the oil spreads out uniformly until it makes an oil slick just one molecule thick, with adjacent molecules just touching, estimate the diameter of the oil slick. Assume the oil molecules have a diameter of 2x10^-10m.

8) Jean camps beside a wide river and wonders how wide it is. She spots a large rock on the bank directly across from her. She then walks upstream until she judges that the angle between her and the rock, which she can still see clearly, is now at angle of 30° downstream. Jean measures her stride to be about one yard long. The distance back to her camp is 120 strides. About how far across, both in yards and in meters, is the river?

9) A watch manufacturer claims that its watches gain or lose no more than 8 seconds in a year. How accurate is this watch, expressed as a percentage?

10)  The diameter of the Moon is 3480 km. What is the volume of the Moon? How many Moons would be needed to create a volume equal to that of Earth?

11) An angstrom is a unit of length, defined as 10^-10 m, which is on the order of the diameter of an atom.
(a)    How many nanometers are in 1.0 angstrom?
(b)    How many femtometers or fermis are in 1.0 angstrom?
(c)    How many angstrms are in 1.0 light year

12) How many angstroms are in 1.0 meter?

13) Determine the percent uncertainity in q, and in sin q, when
(a)    q = 15.0° +/- 0.5°

(b)    q = 75.0° +/- 0.5°

Thank you for helping. I figure this is a lot, but I appreciate your help.
This is a part of my Physics and I please need the answers.
I know you will not let me down

## #8 Re: Help Me ! » Simplify expression Math » 2007-08-26 13:20:47

Thank you JaneFairfax   Even after the replies were posted you took your time to answer me.
Thankx once again.

Thank you Identity & John E. Franklin, for admitting that you were WRONG in certain areas of the Math answers. Thank you for your honesty. Honesty is important. Remember ENRON !

## #9 Help Me ! » Simplify expression Math » 2007-08-22 07:53:02

tonyz1949
Replies: 11

1.    [    2x/ (x^2  - 6x + 9)   -    1/(x+1)   - 8/ (x^2 - 2x - 3)  ]

2.  sq.rt x/ x

3.  ln e^7

4.  e ^(ln 3)

5.  3 (n +1) ! / (5n !)

6.     1/(3+x)  -  1/3
---------------------------
x

7.   e ^ (1 + ln x)

8.  e^ (3 ln x)

Thank you for helping me.

## #10 Re: Help Me ! » Math question » 2007-08-22 06:54:09

Thank you pi man and John E. Franklin for the reply.  It's OK. Better late than never.  I thank you both very much for helping me.  I am preparing for my SAT.

## #11 Help Me ! » Averages » 2007-08-14 05:49:41

tonyz1949
Replies: 3

The average (arithmetic mean ) of four different positive integers is 9. If the first of these integers is 3 times the second integer and the second integer is 2 less than the third integer, what is the least possible value of the fourth integer?

(A)  5
(B)  4
(C)  3
(D)  2
(E)  1

Thank You pi man

## #13 Re: Help Me ! » Integers » 2007-08-10 01:30:16

Thank You bossk171

## #14 Re: Help Me ! » Square » 2007-08-10 01:18:19

Thanks a bunch pi man

## #15 Re: Help Me ! » Distance » 2007-08-10 01:12:12

Thank you bossk171. Hope that works

## #16 Re: Help Me ! » Permutation/Combination » 2007-08-10 01:10:14

Thank You piMan;)

## #17 Re: This is Cool » Microsoft Math 3.0?? » 2007-08-09 14:01:00

thank you for yr answer.  I really am preparing for my SAT and am soooo busy.

## #18 Help Me ! » Set Notation » 2007-08-09 13:50:30

tonyz1949
Replies: 2

Sets A, B, and C have 6 members in common. Sets A and B have a total of 17 members in common. Sets B and C have a total of 10 members in common. If each member of set B is contained in at least one of the other two sets, how many members are in set B?

## #19 Help Me ! » Permutation/Combination » 2007-08-09 13:48:35

tonyz1949
Replies: 2

How many different teams of 2 people each can Joshua select from a group of 5 people?

tonyz1949
Replies: 2

tonyz1949
Replies: 2

## #22 Help Me ! » Distance » 2007-08-09 13:29:18

tonyz1949
Replies: 2

Yolanda walked a distance of 3 miles in 90 minutes. If her speed for the first mile was 6 miles per hour, how many minutes did it take her to walk the rest of the distance?

## #23 Re: This is Cool » Microsoft Math 3.0?? » 2007-08-07 16:36:19

Hi I am new here to the forum.  Pls tell me how did you upload the picture to the forum.

Thank you.

## #24 Help Me ! » Math question » 2007-08-04 17:57:29

tonyz1949
Replies: 3

1.    Tang-E drink contains 45 percent orange juice by volume. Which of the following expressions represents the percent of orange juice by volume in a mixture of t gallons of Tang-E drink and w gallons of water?