By using this site, you agree to our Privacy Policy and our Terms of Use. Close

Forums - General Discussion - Who's up for some math problems?

Gnizmo on 23 December 2008

A is 11, B is 4, C is 6. Too easy.



Starcraft 2 ID: Gnizmo 229

Around the Network
twesterm on 23 December 2008

High School Math hmmm?

Consider the following limit:

limx->+∞ x5[sin(1/x) - 1/x + 1/6x3]

  1. Evaluate the limit
  2. Evaluate the limit using L'Hospital's Rule

-edit-

changed it a little to make it fair (should make #1 super easy ), no cheating!



 

Tyrannical on 23 December 2008
Gnizmo said:

A is 11, B is 4, C is 6. Too easy.

 

 OK, a harder one

 

A * B * C = 528

A * C = 78

B * C = 84



Yet, today, America's leaders are reenacting every folly that brought these great powers [Russia, Germany, and Japan] to ruin -- from arrogance and hubris, to assertions of global hegemony, to imperial overstretch, to trumpeting new 'crusades,' to handing out war guarantees to regions and countries where Americans have never fought before. We are piling up the kind of commitments that produced the greatest disasters of the twentieth century.
 — Pat Buchanan – A Republic, Not an Empire

Tyrannical on 23 December 2008
twesterm said:

High School Math hmmm?

Consider the following limit:

limx->+∞ x5[sin(1/x) - 1/x + 1/6x3]

  1. Evaluate the limit
  2. Evaluate the limit using L'Hospital's Rule

-edit-

changed it a little to make it fair (should make #1 super easy ), no cheating!

 

 

I've long since purged calculus from my mind. But I'm pretty sure it goes back and forth from neagtive infinity to positive infinity.



Yet, today, America's leaders are reenacting every folly that brought these great powers [Russia, Germany, and Japan] to ruin -- from arrogance and hubris, to assertions of global hegemony, to imperial overstretch, to trumpeting new 'crusades,' to handing out war guarantees to regions and countries where Americans have never fought before. We are piling up the kind of commitments that produced the greatest disasters of the twentieth century.
 — Pat Buchanan – A Republic, Not an Empire

Gnizmo on 23 December 2008

Dealing with decimals is just obnoxious.The problem is solved in almost an identical manner but the numbers aren't as neat. All answers are thus approximate to two decimal places. A 6.28, B is 6.77, and C is 12.41.



Starcraft 2 ID: Gnizmo 229

Around the Network
fuegonian on 23 December 2008
TheLivingShadow said:
Hey guys sorry I'm a little late but here goes the answer to all the problems you posted...which were laughably easy except for the horse one which is a little stronger.
colonelstubbs said:
Ive got a maths problem. How do i fit ten horses into nine stables?

I believe this is a possible choice but I'm not sure. You put one horse in the middle of the field and then encircle him inside 8 other stables, like this:

[H][H][H]
[H]H[H]
[H][H][H][H]

Then you have 8 stables making a larger 3x3 stable without the center panel, with the tenth horse in it to complete the stable.

Is it right?

For fuegonian's 3 [ 4 - 3 ( 6 - 7 ) ] = Correct procedure would be:

3[4-3(-1)]=
3[4+3]=
3[7]=
21// As easy as that. Of course it can be done mentally if you have a high enough level.

Now for fuegonian's 5x + 3 (x - y) - y = procedure is:

5x+3x-3y-y=
8x-4y=
4(4x-y)// And that's it.

Let's increase the level a little, ok? Here's an Olympiads first level problem:

If P=1x2x3x4...x50, then the number of factors 2 that P has is: ???

That problem should spice things up a bit.

 

 

 I dont understand your equation? Can you clarify exactly what you're after?

Factors greater than 2? Prime factors? Number of times "2" appears in the list of prime factors?

If it's the last one i guess it's about 47...



I always look for a woman who has a tattoo. I see a woman with a tattoo, and I’m thinking, okay, here’s a gal who’s capable of making a decision she’ll regret in the future.

twesterm on 23 December 2008
Tyrannical said:
Gnizmo said:

A is 11, B is 4, C is 6. Too easy.

 

 OK, a harder one

 

A * B * C = 528

A * C = 78

B * C = 84

 

Simple

  • ABC = x
  • AC = y
  • BC = z

C = z/B
B = z/C

A = y/C
C = y/A

y/C * z/C * C = x
Cyz/C2 = x
yz/C = x
C = yz/x

A * yz/x = y
A = x/z

x/z * B * yz/x = x
Byz/x = z
B = zx/zy = x/y

  • A =x/z
  • B = x/y
  • C = yz/x

Check it, it works

  • ABC = x: x/z * x/y * yz/x = x2yz/xyz = x
  • AC = y:   x/z * yz/x = xyz/xz = y
  • BC = z:   x/y * yz/x = xyz/xy = z


 

twesterm on 23 December 2008
Gnizmo said:
Dealing with decimals is just obnoxious.The problem is solved in almost an identical manner but the numbers aren't as neat. All answers are thus approximate to two decimal places. A 6.28, B is 6.77, and C is 12.41.

 

That's why I said screw it and just used letters. :-p

Tyrannical said:
twesterm said:

High School Math hmmm?

Consider the following limit:

limx->+∞ x5[sin(1/x) - 1/x + 1/6x3]

  1. Evaluate the limit
  2. Evaluate the limit using L'Hospital's Rule

-edit-

changed it a little to make it fair (should make #1 super easy ), no cheating!

 

 

I've long since purged calculus from my mind. But I'm pretty sure it goes back and forth from neagtive infinity to positive infinity.

 

Nope, wrong on both



 

Tyrannical on 23 December 2008
Gnizmo said:
Dealing with decimals is just obnoxious.The problem is solved in almost an identical manner but the numbers aren't as neat. All answers are thus approximate to two decimal places. A 6.28, B is 6.77, and C is 12.41.

 

 Actualy, A is 10, B is 11 and C is 12

I was just trying to be funny using Hex math. I suppse if I said A*B = 6E it would have been too obvious



Yet, today, America's leaders are reenacting every folly that brought these great powers [Russia, Germany, and Japan] to ruin -- from arrogance and hubris, to assertions of global hegemony, to imperial overstretch, to trumpeting new 'crusades,' to handing out war guarantees to regions and countries where Americans have never fought before. We are piling up the kind of commitments that produced the greatest disasters of the twentieth century.
 — Pat Buchanan – A Republic, Not an Empire

twesterm on 23 December 2008
Tyrannical said:
Gnizmo said:
Dealing with decimals is just obnoxious.The problem is solved in almost an identical manner but the numbers aren't as neat. All answers are thus approximate to two decimal places. A 6.28, B is 6.77, and C is 12.41.

 

 Actualy, A is 10, B is 11 and C is 12

I was just trying to be funny using Hex math. I suppse if I said A*B = 6E it would have been too obvious

 

If you're using a different base you should probably denote that.