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

You are not logged in.

## #1 Help Me ! » Help a dad - Triangles » 2005-11-24 01:12:31

robin
Replies: 1

Hi,

My kid brought some homework back and I sat down to help...... And got stuck *blush*
Well, his homework was easy, find the missing length or angle of a triangle etc.  We finished that with no problems and I felt quite happy I seemed to of helped, but then he asked me about angles of a triangle -
Why are the angles always an exact figure, like 45 degrees or 61 degrees.

I should of just said, thats what the book says, but no, I went into explaining that the angles can have decimals and tried to explain about the Angle being built with Degrees and minutes / secs ... This sank in and then he said, -
What tangent should be used for a 32.47 degree angle  ?

I grinned and opened the Trigonometric table page and found 32 degrees = 0.625
and 33 degrees = 0.649.. And said it lies within these too tangents.

But.... I couldn't explain what the exact tangent to use would be. I told him we'd revisit the problem and so here i am.... I've searched the net and havent found any such precise tangent tables or anything which will help me to understand and explain better the solution.

Sorry its a long one... Any help on this would be appreciated.

Robin

## #2 Help Me ! » Rectangular arrangements » 2005-10-28 08:03:35

robin
Replies: 2

Whilst tiling the kitchen, I got to thininking about what shapes could be made with the tiles. in particular rectangles.

For example if I had 15 tiles, how many different arrangements of rectangles could I make.  In this case it was two.

15 tiles = 2 arrangements  1 x 15 and 3 x 5

A stack of  1111 walls tiles   ???

How many rectangular arrangements can be maded using 1111 tiles. Is there a formular for working this out ?

Ive searched for an answer on the net, but haven't found anything to help.

Any pointers would be great

Robin

## #3 Help Me ! » How did Fermat do it ? » 2005-09-23 07:16:06

robin
Replies: 1

Hi,

You have probably all seen or read about Fermat receiving a letter asking if 100895598169 is prime and quickly replying that it was a factor of 112303 and 898423.
Anyway, I was trying to find out how he worked it out. Knowing the answers gives a huge help in finding a method, but don't think he did it the same way.

100895598169 X 8 = 807164785352
Sqrt of 807164785352 =  898423
100895598169 / 898423 = 112303

Can anyone come up with other methods ?

Robin

## Board footer

Powered by FluxBB