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#1 2010-07-07 00:25:06
- Sunrise-Moon
- Scratcher
- Registered: 2009-06-27
- Posts: 1000+
Sine and Cosine Explained?
Could someone explain to me what the sine and cosine do and how to use them?
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#2 2010-07-07 00:29:14
- ChuxXxliciousness
- Scratcher
- Registered: 2010-02-25
- Posts: 90
Re: Sine and Cosine Explained?
They're trig functions, that's pretty much all I know about it and need to know.
Sine make a sideways S shape on a graphing calculator and Cosine makes a U or V shape
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#3 2010-07-07 00:36:50
- Sunrise-Moon
- Scratcher
- Registered: 2009-06-27
- Posts: 1000+
Re: Sine and Cosine Explained?
ChuxXxliciousness wrote:
They're trig functions, that's pretty much all I know about it and need to know.
Sine make a sideways S shape on a graphing calculator and Cosine makes a U or V shape
lol I'm pretty sure it can be helpful to at least know 
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#4 2010-07-07 00:46:15
- ChuxXxliciousness
- Scratcher
- Registered: 2010-02-25
- Posts: 90
Re: Sine and Cosine Explained?
I guess they might come in handy making patterns or something like that, but I've never found a use for them. Maybe I could use it to make wavy text or something xD
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#5 2010-07-07 00:55:07
Re: Sine and Cosine Explained?
Sine, cosine, and tangent are ratios in right triangles used in calculating distance and angles.
They're often used in projects involving things like launching objects based on angles and power.
I know that a lot of people want a block that points a sprite at a specific coordinate. Using trig, you can do that! 
Last edited by Harakou (2010-07-07 01:19:36)
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#6 2010-07-07 01:07:31
- ChuxXxliciousness
- Scratcher
- Registered: 2010-02-25
- Posts: 90
Re: Sine and Cosine Explained?
Well there you have it! lol.
Now if only I had good teachers at my school that would have told me the uses for trig functions. I didn't even do any of the work for the class, just programmed my calculator to do the problems for me. Aced every test that way!
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#7 2010-07-07 01:18:20
Re: Sine and Cosine Explained?
ChuxXxliciousness wrote:
Well there you have it! lol.
Now if only I had good teachers at my school that would have told me the uses for trig functions. I didn't even do any of the work for the class, just programmed my calculator to do the problems for me. Aced every test that way!
On a TI-84? I love those! My friend and I wrote a program that factored trinomials for us.
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#8 2010-07-07 06:42:04
- ScratchReallyROCKS
- Scratcher
- Registered: 2009-04-22
- Posts: 1000+
Re: Sine and Cosine Explained?
Heres a little project I uploaded yesterday:
(link to project)
It shows trig functions in the form of a triangle. Look at the sine and cosine scripts to see how they work.
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#9 2010-07-07 10:07:34
- TimeFreeze
- Scratcher
- Registered: 2008-08-11
- Posts: 500+
Re: Sine and Cosine Explained?
They are actually the only reason that Scratch has the [move 10 steps] block. That block is really this:
[change x by ((sin of direction) * 10)]
[change y by ((cos of direction) * 10)]
The number that you put after * is the number of steps you want it to move.
If it was:
[change x by ((sin of direction) * 7)]
[change y by ((cos of direction) * 7)]
That would be [move 7 steps].
This can be useful for scrolling sometimes.
Hope it helps 
!
Last edited by TimeFreeze (2010-07-07 10:08:21)
There are 10 types of people in this world: Those who understand binary, and those who don't. --[insert unrelated transition]-- GRANDILOQUENCE FTW!
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#10 2010-07-07 10:12:17
- juststickman
- Scratcher
- Registered: 2009-05-31
- Posts: 1000+
Re: Sine and Cosine Explained?
Harakou wrote:
ChuxXxliciousness wrote:
Well there you have it! lol.
Now if only I had good teachers at my school that would have told me the uses for trig functions. I didn't even do any of the work for the class, just programmed my calculator to do the problems for me. Aced every test that way!On a TI-84? I love those! My friend and I wrote a program that factored trinomials for us.
In my school, they gave us a program to do that stuff
TimeFreeze wrote:
They are actually the only reason that Scratch has the [move 10 steps] block. That block is really this:
[change x by ((sin of direction) * 10)]
[change y by ((cos of direction) * 10)]
The number that you put after * is the number of steps you want it to move.
If it was:
[change x by ((sin of direction) * 7)]
[change y by ((cos of direction) * 7)]
That would be [move 7 steps].
This can be useful for scrolling sometimes.
Hope it helps
This is only for scratch. Otherwise you use cos for x and sin for y.
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#11 2010-07-07 15:26:08
- Sunrise-Moon
- Scratcher
- Registered: 2009-06-27
- Posts: 1000+
Re: Sine and Cosine Explained?
Ok, I see the use for it now. Thanks
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