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**FunnyProject****Scratcher**- Registered: 2010-09-19
- Posts: 2

I'm great at maths with things like 89364

+ 61839

______

151203

1111

But rubbish with cos, sin, e^ and all that other stuff. All of the descriptions so far are still a bit complicated, so I'm as stuck as someone who's been hit in sticky glue. Any help with what would happen if you did a certain thing with each mathematical function?

<change{ my life on scratch }by( about 1000000000

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**Paddle2See****Scratch Team**- Registered: 2007-10-27
- Posts: 1000+

## ty44 wrote:

<abs( 1 )>

How do you get red "abs" blocks in scratch?

[/blocks]

The red blocks are obsolete blocks...meaning that they are no longer used in Scratch. "abs" used to have it's own block...but then it became one of the functions you can get from the drop-down menu. You can maybe still find the old style in an older project. But be careful - they might not work any more.

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## dingdong wrote:

I'm probably the youngest "good" scratcher on this website, oh yeah I learned scrolling in steps from you, so thanx

Ahem.

*coughialsomakegoodprojectsijustneverbothertopostthemonthesitesbecauseidontfeellikeitandmostofthemarejusttestsandim1yearyoungerthanyoucough*

bye

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## nextstorm wrote:

## dingdong wrote:

I'm probably the youngest "good" scratcher on this website, oh yeah I learned scrolling in steps from you, so thanx

Ahem.

*coughialsomakegoodprojectsijustneverbothertopostthemonthesitesbecauseidontfeellikeitandmostofthemarejusttestsandim1yearyoungerthanyoucough*

Dude, you signed up way after this post was made.

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## dingdong wrote:

Moderator Summary:

Sine (sin), cosine (cos), and tangent (tan) are trigonometric functions. They are useful in projects concerning direction. To read more about trigonometry you can view the wikipedia article here.

If you have further, specific questions about these blocks you can ask on this topic.I have been taught in my algebra class how to use these formulas, but my math teacher didn't mention how to use the formulas on just numbers. So how do I use this formula?

because I still don't understand how I scroll in steps

/ \ / \

<change X by I sin of direction * 1 I * I speed * -1 I>

\ / \ /

/ \ / \

<change Y by I cos of direction * 1 I * I speed *-1 I>

\ / \ /

Wait! Thats the same as:

/ \ / \

<change X by I sin of direction I * I speed * -1 I>

\ / \ /

/ \ / \

<change Y by I cos of direction I * I speed *-1 I>

\ / \ /

Because direction * 1 is the same as direction am i the only one here who sees this? I am NOT good at math BTW I saw someone answer someone on this once though, so that how I figured it out.

*Last edited by Pecola1 (2011-04-27 21:21:56)*

If you are reading this, please read to the end, because if you don't you won't know what's at the end. Don't just skip to the end though otherwise you won't be able to read the middle, which is most important. Now you must be wondering why you just read all that, the reason is you may have not noticed something, read it again and see if you notice it this time

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Man, I still don't really understand how can cos and sin determine how much a piece can spin around it's axis. I know it has something to do with the x y graph but I don't understand how you can calculate a formula to spin an piece for a certain amount.

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**CosmicProjectz****Scratcher**- Registered: 2011-03-25
- Posts: 100+

Aaaaahhhhhhh So Many Numbers Im So Confused Im In 4th Grade Only!!!!!!!!

Good show.

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**CosmicProjectz****Scratcher**- Registered: 2011-03-25
- Posts: 100+

Just randomly experiment. It's what I do, and it works!

Good show.

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**CosmicProjectz****Scratcher**- Registered: 2011-03-25
- Posts: 100+

## FunnyProject wrote:

I'm great at maths with things like 89364

+ 61839

______

151203

1111

But rubbish with cos, sin, e^ and all that other stuff. All of the descriptions so far are still a bit complicated, so I'm as stuck as someone who's been hit in sticky glue. Any help with what would happen if you did a certain thing with each mathematical function?

<change{ my life on scratch }by( about 1000000000

Dude, 89364 plus 121203 is SOOOOOO easy.

Good show.

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## dingdong wrote:

I'm probably the youngest "good" scratcher on this website, oh yeah I learned scrolling in steps from you, so thanx

I'm even younger.

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**daychicken****Scratcher**- Registered: 2010-04-23
- Posts: 1

How do I change a 2D vector (X,Y) into a direction (D)?

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## daychicken wrote:

How do I change a 2D vector (X,Y) into a direction (D)?

[blocks]

<when green flag clicked>

<forever>

<set{ X }to( <direction>

<set{ Y }to( <direction>

<end>

[/blocks]

There you go

*Last edited by TVflea (2011-10-20 23:23:46)*

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## daychicken wrote:

How do I change a 2D vector (X,Y) into a direction (D)?

Since TVFlea's answer had nothing to do with this, I'll answer it.

What you're looking for a is a script that changes two variables, the X and Y of a vector into a direction...

Not a script to go random directions forever.

I hope you mean that x=positive and y=0 being 0 degrees, and x=negative and y=0 being 180. If not, just subtract 90 or however many degrees you want.

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**mythbusteranimator****Scratcher**- Registered: 2012-02-28
- Posts: 1000+

I'm twelve and doing 9th grade math, so I did pre-trig two years ago and understand everything. But, I don't understand what use sine and cosine have in scratch. I've seen some games shooting cannonballs and that type of stuff, and I've seen sine and cosine when I download, but I do not get how I'd be able to create an arc.

[scratchblocks]

when I recieve (shoot)

forever

change X by (sine) of X

change X by (cosine) of X

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**jji7skyline****Scratcher**- Registered: 2010-03-08
- Posts: 1000+

You should use [scratchblocks]

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## Paddle2See wrote:

## ty44 wrote:

<abs( 1 )>

How do you get red "abs" blocks in scratch?

[/blocks]

The red blocks are obsolete blocks...meaning that they are no longer used in Scratch. "abs" used to have it's own block...but then it became one of the functions you can get from the drop-down menu. You can maybe still find the old style in an older project. But be careful - they might not work any more.

you should use the new block look (

when gf clicked say ([abs v] of (-5))) instead of the old one which looks like

<when green flag clicked>

<say> <abs( -1 )>

*Last edited by iTweak0r (2012-04-18 11:33:33)*

Make it in Scratch! because it's cooler when it's made in scratch

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## dingdong wrote:

HEY!

I iz a sig. So there. CLICK ME ITS SO IMPORTANT!!!!

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This is confusing.... i mean, the sin cos tan, not the explanation...

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**mythbusteranimator****Scratcher**- Registered: 2012-02-28
- Posts: 1000+

## chongyian wrote:

This is confusing.... i mean, the sin cos tan, not the explanation...

It was hard for me to understand, but now i got it.

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**legobob23o****Scratcher**- Registered: 2012-06-22
- Posts: 500+

Ooooooooooooo bumpeh! (I mean "Bump")

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**firedrake969_test****Scratcher**- Registered: 2012-08-08
- Posts: 500+

## playzooki wrote:

## dingdong wrote:

HEY!

No need to get into an argument.

Bump.

Alt of Firedrake969.

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