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#42501 Re: Help Me ! » Math Study Tips... » 2005-10-06 20:50:22
Understand the logic. Learn the techniques. Remember the formulae. Practice methods of proving. Most important, hone your calculation skills and never forget the fundamental concepts.
#42502 Re: Help Me ! » help plz » 2005-10-06 20:39:22
Yes, very much British 
#42503 Re: Help Me ! » help plz » 2005-10-06 16:13:35
In India,
y = mx + c
where c is the y intercept and -x/y is the slope (or gradient),
when written as y - mx - c = 0
#42504 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-06 16:03:32
Problem # k + 24
A cube is made by cutting off the excess portions of a sphere of radius r. What is the volume of the biggest cube that can be formed?
#42505 Jokes » Tips to improve your writing » 2005-10-06 00:06:21
- Jai Ganesh
- Replies: 13
1. Avoid alliteration. Always.
2. Never use a long word when a diminutive one will do.
3. Employ the vernacular.
4. Eschew ampersands & abbreviations, etc.
5. Parenthetical remarks (however relevant) are unnecessary.
6. Remember to never split an infinitive.
7. Contractions aren't necessary.
8. Foreign words and phrases are not apropos.
9. One should never generalize.
10. Eliminate quotations. As Ralph Waldo Emerson said, "I hate quotations. Tell me what you know."
11. Comparisons are as bad as cliches.
12. Don't be redundant; don't use more words than necessary; it's highly superfluous.
13. Be more or less specific.
14. Understatement is always best.
15. One-word sentences? Eliminate.
16. Analogies in writing are like feathers on a snake.
17. The passive voice is to be avoided.
18. Go around the barn at high noon to avoid colloquialisms.
19. Even if a mixed metaphor sings, it should be derailed.
20. Who needs rhetorical questions?
21. Exaggeration is a billion times worse than understatement.
22. Don't never use a double negation.
23. capitalize every sentence and remember always end it with point
24. Do not put statements in the negative form.
25. Verbs have to agree with their subjects.
26. Proofread carefully to see if you words out.
27. If you reread your work, you can find on rereading a great deal of repetition can be avoided by rereading and editing.
28. A writer must not shift your point of view.
29. And don't start a sentence with a conjunction. (Remember, too, a preposition is a terrible word to end a sentence with.)
30. Don't overuse exclamation marks!!
31. Place pronouns as close as possible, especially in long sentences, as of 10 or more words, to the irantecedents.
32. Writing carefully, dangling participles must be avoided.
33. If any word is improper at the end of a sentence, a linking verb is.
34. Take the bull by the hand and avoid mixing metaphors.
35. Avoid trendy locutions that sound flaky.
36. Everyone should be careful to use a singular pronoun with singular nouns in their writing.
37. Always pick on the correct idiom.
38. The adverb always follows the verb.
39. Last but not least, avoid cliches like the plague; They're old hat; seek viable alternatives.
#42506 Re: Dark Discussions at Cafe Infinity » Wink Murder 4 » 2005-10-04 23:15:39
Playing
justlookingforthemoment
MathsIsFun
Mathsyperson
Zach
insomnia
Ganesh may be added to the list
#42507 Re: Guestbook » tanks » 2005-10-04 23:13:37
#42508 Re: Help Me ! » combinatorics in playing cards - 52 caard standard deck » 2005-10-04 23:08:43
I think the required probability is
(32 x 28 x 24)/(52 x 51 x 50) assuming the raminaing two cards can be either paired or unpaired, greater or lesser than nine.
#42509 Re: Help Me ! » Algebra in Standard form.. » 2005-10-04 22:34:35
The slope of 4x-2y+7=0 is 2.
Therefore, the perpendicular to this line has a slope -1/2.
The y-intercept 2x+3y-10=0
is 10/3.
Therefore, the line passes through (0, 10/3)
The equation of the line would be
y - 10/3 = -1/2(x - 0) = -x/2
2y - 20/3 = -x
x + 2y - 20/3 = 0
3x + 6y - 20 = 0 is the required equation.
#42510 Re: Help Me ! » Need help in this problem... » 2005-10-04 16:57:53
Given two points, the equation of the line joining the points is
(y-y1)/(y2-y1) = (x-x1)/(x2-x1)
Substituting y1 = 5, y2 = -1, x1 = 3 and x2 = -3, the equation of the line is
x-y+2 = 0,
The slope of this line m=(y2-y1)/(x2-x1), i.e., m = 1.
The slope of a line perpendicular to this line would be -1
(Because, if two lines are perpendicular, the product of their slopes is -1).
The midpoint of U(3,5) and V(-3, -1) is given by
[(x1+x2)/2, (y1+y2)/2]
Therefore, the midpoint of the line UV is
(0,2).
The equation of a line of given slope passing through a given point is
(y-y1) = m(x-x1)
We know, m=-1 for the perpendicular line.
Therefore, the equation of the perpendicular bisector is
(y-2) = -1(x-0)
or
x+y-2 = 0
Substitute the x and y coordinates of point W(2,-1) in this equation.
We see that it does not satisfy the equation.
Therefore, the point does not lie on the perpendicular bisector.
#42511 Re: Help Me ! » hel[p me with this problem » 2005-10-04 16:04:36
196
---- = 14
F
Therefore,
196
---- = F
14
When 196 is divided by 14, we get 14.
Therefore,
F = 14
#42512 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-09-30 18:27:51
Mathsy, all your solutions are correct! You had understood problem # k + 16 rightly!
#42513 Re: Dark Discussions at Cafe Infinity » Wink Murder 3 » 2005-09-30 18:14:17
Me too playing
#42514 Re: Help Me ! » Orders of Operation Help » 2005-09-30 18:04:27
Step 1 : Do Operations within the Parentheses
3 - (6 + 8) x 3 = 3 - 14 x 3 = 3 - 42 = -39
The first operation to be done is always the one within the Parantheses.
Step 2 : Do Operations with Powers and Roots
3 + 2^5 = 3 + 32 = 35 (Here ^ represents powers)
3 + √ 16 = 3 ± 4 = 7 or -1.
Step 3 : Do all multiplication and division operations from left to right
Step 4 : Do all addition and subtraction operations from left to right
50 ÷ 10 ÷ 2 = (50 ÷ 10 ) ÷ 2 = 5 ÷ 2 = 2.5
If it is done from the other direction, you get a different (and wrong) answer.
#42515 Re: This is Cool » pi: the phantom of mathematics » 2005-09-26 16:01:36
Euler's equation!
This is because
(Cosθ + iSinθ)^n = Cos(nθ) + iSin(nθ)...DeMoivre's equation
and Cosθ + iSinθ=e^(iθ)
When θ=Pi (radians)
e^(i*pi) = Cos(pi) + iSin(pi)
We known Cos(pi)=-1 and Sin(pi)=0,
Therefore,
e^(i*pi)=-1
or
e^(i*pi) + 1 = 0
#42516 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-09-19 16:07:22
Problem # k + 23
A Pythagorean triple is a set of three numbers (a,b,c) such that
a² + b² = c². For example, (3,4,5).
Prove that three prime numbers cannot form a Pthagorean triple.
#42517 Re: Puzzles and Games » Simple Logic Puzzle; The Farmer. » 2005-09-18 17:29:57
The additional worker is accomodated and the earlier arrangement is changed into this formation:-
4 workers 5 workers 6 workers
5 workers The house 6 workers
6 workers 6 workers 3 workers
Just a guess
#42518 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-09-18 16:10:43
solved problem #k+20 (finnaly, I think)
And solved it correctly! Well done, Kylekatarn!!!
And the solution to problem # k + 2 is a much smaller number!
It is
#42519 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-09-15 17:09:20
#42520 Re: Help Me ! » Help in Math Induction Question » 2005-09-15 02:04:44
Put n=7.
7mod6=1
7^3mod6=343mod6=1
Put n=8
8mod6=2
8^3mod6=512mod6=2.
Assume this is true for k.
Therefore, kmod6=k^3mod6.
Try for k+1.
Lets say (k+1)mod6=m
(k+1)^3mod6 = (k^3 + 3k^2+3k+1)mod6.
= (k^3+3k^2+2k+k+1)mod6= (k^3+2k^2+k^2+2k+k+1)mod6
= {[k²(k+2)+k(k+2)]+k+1}mod6
= {[(k²+k)(k+2)] +k+1}mod6
={[(k(k+1)(k+2) + k+1}mod6
We know that k(k+1)(k+2) is divisble by 6 for any k>1, k∈N,
Hence the above is reduced to
(k+1)mod6
It is seen that it is true for k+1, hence, it is true for any value of k.
q.e.d
#42521 Re: Help Me ! » very easy problem solving, but I'm just soooooooo bad at this » 2005-09-14 23:45:45
How about this one?
= {m - [1/3m -4] - [m/6 -2] /2} -2
The result is given: m/4+1
= {m - [1/3m -4] - [m/6 -2] /2} -2
= { 2/3m +4 - [m/6 -2] /2} -2
= { 2/3m +4 - [m/6 -12/6] /2} -2
= {2/3m +4 - m/12 +1}-2
= {2/3m - m/12 + 5} - 2
= 11/12m + 5 - 2
= 11/12m + 3
= (11m+36)/12
#42522 Re: Maths Is Fun - Suggestions and Comments » The math tag » 2005-09-14 22:13:14
Great....
It would take some time to be familiar with the codes
#42523 Re: Help Me ! » very easy problem solving, but I'm just soooooooo bad at this » 2005-09-14 22:10:43
#42524 Re: Help Me ! » very easy problem solving, but I'm just soooooooo bad at this » 2005-09-14 20:42:46
by_Faizah=m-(1/3m-4)/4-3
This should be written as {[m-(1/3m-4)]/4}-3
= {[m - 1/3m +4]/4}-3
= {[2/3m+4]/4}-3
= {[(2m+12)/3]/4}/ - 3
= {[2m+12]/12} - 3
= {[2m+12]-36}/12
= {2m - 24}/12
= m/6 - 2
#42525 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-09-14 18:07:57
Your are correct, John!
