Math Is Fun Forum
  Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

#2 Re: Help Me ! » cardinality of primes » 2013-07-30 09:38:01

I know about those theorems, I also know  that infinite sets can have same cardinality as their proper subsets,I wanted to know if |P| = |N| then what is the bijection between them?

#3 Help Me ! » cardinality of primes » 2013-07-30 04:41:38

{7/3}
Replies: 6

if P is the set of primes then is |P| = |N| true?

#4 Re: Help Me ! » Algebraic problem. » 2013-07-05 23:48:40

Ebenezerson I think u are posting wrong question

#5 Re: Introductions » My greetings » 2013-07-05 13:43:26

hi ebnezerson
welcome to the forum

#6 Re: Help Me ! » logarithm » 2013-07-05 00:09:28

I want a proof that b for every positive b and n there is a real number x such that b^x=n

#7 Re: Help Me ! » logarithm » 2013-07-04 20:43:54

sorry forgot to say positive

#8 Help Me ! » logarithm » 2013-07-04 16:05:57

{7/3}
Replies: 4

prove that if r is real,then log r is real.

#9 Re: Help Me ! » factoring a polynomial » 2013-07-04 04:39:55

my old textbook says gcd(a/b,c/d) = gcd(a,c)/lcm(b,d)

#11 Re: Help Me ! » factoring a polynomial » 2013-07-03 12:57:18

Al-Allo wrote:

Ah ok, but parallely, if I said :

I'm not sure about it, but could we say that the common factor of these two is 7 ??? Or I'm totally wrong ?

hi al-allo  first number is divisible by 1/7 and the second one by 7

#14 Help Me ! » an easy question » 2013-07-01 17:44:01

{7/3}
Replies: 4

I can't see any way to solve this
prove,a+bi=c+di implies a=b and c=d

#16 Re: Help Me ! » Sine Inverse » 2013-06-29 16:46:44

Sin A=a/c and sin B=b/c then a=b ,so in two right triangles with angle A and B ,oposite side is a=b,hypottenuse is c,other side must be equal.thus two triangles are congruent,A=B

#17 Re: Dark Discussions at Cafe Infinity » You might be a mathematician if » 2013-06-29 16:43:04

Agnishom wrote:

Okay, but how many of them apply to you

only 3

#18 Re: Dark Discussions at Cafe Infinity » You might be a mathematician if » 2013-06-29 15:18:10

I have to do all that to become a mathematician! It's easier to think that i am a mathematician.

#19 Re: Help Me ! » locus in co-ordinate geometry » 2013-06-28 18:32:08

Sorry,i mixed up locus and envelope.

#20 Re: Help Me ! » locus in co-ordinate geometry » 2013-06-28 13:50:15

Not sure,but won't the locus be a segment of a parabola?

#21 Re: Help Me ! » complex number problem » 2013-06-28 05:06:07

I'm assuming u mean abs(z) by IzI in which case z=a+bi.Re(z)=a and abs(z)=square root of a^2+b^2
now,a^2<a^2+b^2 [equal in case of b=0] taking positive square root |a|<abs(z),by the inequality law of absoloute value,-abs(z)<a<abs(z)

#23 Re: Introductions » Hello ^^ » 2013-06-26 21:03:34

Hi bronxsystem
welcome to the forum

#24 Re: Help Me ! » Summation Proof » 2013-06-26 01:43:52

Turn the summation to this

then divide it by
you can then prove it.

#25 Re: Help Me ! » Tautology and contradiction » 2013-06-25 01:43:55

Okay,what about tautology?and contradiction in proofs is only used in the form -p and (not p)

Board footer

Powered by FluxBB