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#1776 Re: Puzzles and Games » Grrrr !!!!!!!!!!!!!!! Help A.s.a.p » 2011-09-01 04:48:31

A man on a park bench is looking at a small portrait. You ask him, "Who is that in the picture?"

The man says, "Brothers and sisters, I have none, but that man's father, is my father's son."

No brother or sisters.
Although the man in the picture's father is my father's son. His father's son is only himself, so the picture man is his child.

#1777 Re: Guestbook » Harry Potter » 2011-09-01 03:45:41

I feel that Harry Potter is one of the best book series available. To the original poster, my favorite character is either Harry or Hermione.

#1778 Re: This is Cool » Trig Functions » 2011-09-01 00:49:00

anoni, who are you talking to?
Oh wait, maybe they deleted their post.

#1779 Re: Help Me ! » Calculus problem. » 2011-09-01 00:41:01

ex2 is not integrable by normal means of anti differentiation. However, in double integrals it is possible to reverse the order of integration to solve an otherwise impossible integral.

#1781 Re: Help Me ! » Calculus problem. » 2011-09-01 00:26:50

I knew that the limits would be confusing...

[0,1] and [3y,3]

#1782 Re: Jai Ganesh's Puzzles » Oral puzzles » 2011-09-01 00:24:34

#1203
4m
#1204
20000
#1205
6.5 km/h
#1206
3km
#1207
22km/h

#1783 Re: Help Me ! » Calculus problem. » 2011-09-01 00:18:52

Another calculus problem...
Solve:
∫0^1∫3y^3e^x^2dxdy

I believe its:
(e9-1)/6

#1784 Re: Help Me ! » Calculus problem. » 2011-09-01 00:11:40

Oh and thanks for the gold star, it would be impossible for me to make that (I am horrible at art).

#1785 Re: Help Me ! » Calculus problem. » 2011-09-01 00:10:39

Well, I wouldn't state exactly that I am smarter than my teacher. Jacob Barnett maybe, but surely not me. But it may be true, and if it is, it would be even worse for me. As my teacher has a huge superiority complex.

#1787 Re: Help Me ! » Calculus problem. » 2011-08-31 23:54:05

bob, perhaps. Or the fact that she despises me severely, similar to most of my other teachers (although I am very rule-abiding).

#1788 Re: Help Me ! » Calculus problem. » 2011-08-31 23:10:07

Oh and yes, sorry for the typing mistake bob. I just typed everything my teacher told me, and she usually tries to make me fail by giving the question without including exponents.

#1789 Re: Jai Ganesh's Puzzles » Algebra » 2011-08-31 23:03:06

Thank-you. By the way, how come you stopped adding more questions to this? Its quite fun and challenging.

#1790 Re: Help Me ! » Calculus problem. » 2011-08-31 23:00:06

Thank you everyone for tyour help.
bob, yes, I have promised myself not to teach her anything either (its surprising how much teachers learn rom the tudents while it should be the contrary).

Bundy, yes it does get fairly lonely I suppose. Although it is fun.

By the way, even though both my answers were right,my idiotic teacher gave me 1/2......

#1791 Re: Jai Ganesh's Puzzles » Algebra » 2011-08-31 13:50:59

#1
3, 4, 5
#2
m=-2
#4
3,5
#5
2
#6
(a)

#1792 Re: Jai Ganesh's Puzzles » 10 second questions » 2011-08-31 13:40:10

#3185 60 hours
and the rest...
15 days
26 tonnes
64 cm 17 m
28% 5.6%
14.285%

#1793 Re: Help Me ! » Calculus problem. » 2011-08-31 13:30:08

A few more questions by the way.
A strange and unusual particle moves with velocity equal to v(t)=t10•ln(t) m/s. You observe this particle carefully in a lab and find that over the time interval [1, e1/11] the particle moves how many meters?
I believe its 1/121.

#1794 Re: Jokes » Chemistry » 2011-08-31 13:27:30

Here's one (you may have heard it before though):
A neutron went to a restaurant and asked the price for a soda.
The waiter replied: For you no charge.

#1795 Help Me ! » Calculus problem. » 2011-08-31 13:18:27

ShivamS
Replies: 42

Okay, university classes, I have a teacher who thinks that a supposedly "arrogant" student like me should not be allowed to go to university at this age... So she rarely ever teaches me anything, but does give me some hard problems to answer. So for this one, I was a bit confused. Can anyone please help me? Thanks in advance.

A car travels along the path such that the displacement vs. time (meters vs. seconds) graph is given by the equation: x(t)= (6/π)sin-1t•cos-1t. What is the instantaneous velocity of the car at the point (1/2, π/3)?

I am fairly sure that the answer is 2/√3 m/s, but can someone please help me if that isn't the correct answer?

#1796 Re: Help Me ! » Cube-n-ometry???? » 2011-02-18 03:07:50

If you are confused by the formula used in the definition:
1. Pick a random 2d square on the cube (a face).
2. Find the length (or width)of that square.
3. Square the length (length^2). That means length*length. And since on a square the length and width are equal, the total is the area of that square.
4. Multiply the total by 6, since a cube has 6 faces (which are all squared).

#1797 Re: Help Me ! » How do i work out an average? » 2011-02-10 14:27:36

Three ways:
Mean: Add set of numbers and divide by the number of numbers in the set
Mode=14/3
Median: Middle number in the set. If there are 2, divide their total by 2
Mode: Number which occurs the most

#1798 Re: Help Me ! » finding the missing side of a triangle » 2011-02-10 14:22:47

@holly: Order doesn't matter because addition is commutative, but you cannot put opposite+adjacent=hypotenuse
You can switch opp and ad, but hyp you can not.

#1799 Re: Help Me ! » When will Car B catch Car A after a delayed start? » 2011-02-10 14:12:06

Its quite simple actually. It has been explained, just going to explain it another way though (open your Windows Calculator):
1. 45m = 3/4h = .75
2. 35s*0.75 = 26.25
3. So in 45m car A traveled 26.25 km.
4. Car B is 15s faster.
5. So when car A has traveled 26.25km, car B starts.
6. Next you can do trial/error.
7. 1h has passed. 26.25+35=61.25km traveled by car A
8. 50  km traveled by car B.
9. Then we see we need about 10 more km. So increase 2 quarter hours. Then 3. Thats when you realize car B has traveled more then car A at 1 3/4 hours.
This method is a bit more complicated though.

#1800 Re: Help Me ! » Can You Solve this One? » 2011-02-10 12:10:50

Question:
G = I + 3
I = ?
B = ?
Answer:
G = I + 3 + 12
I = 9
B = 9
12 + 9 + 9 = 30
Strategy: Trial/Error

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