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.

#128 Re: Help Me ! » Help me prove this » 2013-05-23 14:27:51

That was an awesome proof,but i need one more favor,if f'(x)=f(x) and f(0)=1 than f(x)=a^x for some constant a,how do i prove this?

#129 Re: Help Me ! » Help me prove this » 2013-05-22 23:50:21

Proof from first principles will be better

#130 Help Me ! » Help me prove this » 2013-05-22 18:42:10

{7/3}
Replies: 10

Help me prove this:

for some constant a[i cannot use the fact this is ln(x)]

#131 Re: Help Me ! » Limit related proof » 2013-05-22 01:31:55

Thanks,bobbym,my friend liked the proof and i liked the link.

#132 Re: Help Me ! » Limit related proof » 2013-05-21 15:32:03

I think he wants proof of the composition law

#134 Re: Help Me ! » Limit related proof » 2013-05-21 14:01:08

No,i meant limit of f(g(x)) as x approaches a is equal to limit of f(y) as y approaches b.

#135 Re: Help Me ! » does anyone know logic? » 2013-05-20 23:16:12

I believe these are the answer:
a2  b5  c1  d6  e8  f4  g7  h3.

#136 Help Me ! » Limit related proof » 2013-05-20 21:08:40

{7/3}
Replies: 8

My friend wants proof of this statement but i don't know how to prove it,can anyone help- If the limit of g(x) as x tends to a is b than the limit of f(g(x)) as x tends to a and the limit of f(y) as y tends to b is same

#137 Re: Help Me ! » does anyone know logic? » 2013-05-20 16:26:07

I'm not very good at english,do you want to match the two kinds of statements?

#138 Re: Help Me ! » sigma function » 2013-05-20 03:47:28

It's okay,and i know there are many other cases but i wanted to give johnathon some facts so that he can make a strategy and solve it himself

#139 Re: Help Me ! » Continuous functions » 2013-05-20 01:28:02

Thanks for the advice,bob bundy,i will try it.

#140 Re: Help Me ! » Continuous functions » 2013-05-20 00:23:29

I know how to prove linear functions are continuous

#142 Re: Help Me ! » Continuous functions » 2013-05-19 22:28:07

I'd love to go to that link but for some reason the link's words look weired and i can't read them.

#143 Help Me ! » Continuous functions » 2013-05-19 18:43:24

{7/3}
Replies: 9

I have been give a function f(x)=3x^3+x-2,how do i show it is a continuous function?

#144 Re: Help Me ! » sigma function » 2013-05-19 18:40:54

Well, n and n+1 don't have any common primes,which can be a starting point

#145 Re: Help Me ! » sigma function » 2013-05-19 17:52:24

Hi,johnathon bresly,do you know the formula

#146 Re: Help Me ! » Maximise this! » 2013-05-19 12:53:21

Hi,bob bundy,that's what i did too.

#147 Re: Help Me ! » Maximise this! » 2013-05-19 04:38:27

I have proved it,but i used calculus,do you want it?

#148 Re: Help Me ! » A confusing money puzzle » 2013-05-19 04:37:05

Did the jeweler buy or made the necklace using $200 rupees?

#149 Re: Help Me ! » A confusing money puzzle » 2013-05-19 03:27:28

I think it's either 800 or 1000

#150 Re: Help Me ! » Function » 2013-05-18 22:54:53

Oh,thanks,i thaught x^2 was the only one.

Board footer

Powered by FluxBB