[jameshewitt]

shaky on the differential equations questions (some of them) but everything else should be grand

[TheNoobyPotato]

(Original post by Arva)
Yep, but the two angles between a vector will always add up to 360 degrees - so if the result you get is more than 270, you can tell that the other angle is less than 90 and thus acute.

So if its above 90 but below 180, you would do 180 - Ans. If it was above 270, you would do 360 - ...

Right?

[Jack_Smith]

Rise and Shine Everyone! Wake up to another c4 morning! =D

[Akbar2k7]

Today I must do a lot of chem 5 revision, some Bio 5 revision and at least one C4 paper.

I got a U in my first C4 paper then I got a C I am aiming for a B or higher.

[Llewellyn]

(Original post by TheNoobyPotato)
So if its above 90 but below 180, you would do 180 - Ans. If it was above 270, you would do 360 - ...

Right?

You're doing a cosine function. The angle you find will never be greater than 180 degrees. There's no point in trying to overcomplicate the scalar product. There is one angle which you will get by simply using the inverse cosine function.

There cannot be multiple angles for vectors. Remember, vectors have direction so there is only one angle that is made between them. Don't get vectors confused with Cartesian equations.

[grazie]

(Original post by Jack_Smith)
Rise and Shine Everyone! Wake up to another c4 morning! =D

Arva ->

[dodecapus]

Thanks for the pos rep yesterday guys. Another fun day of integration!

[Lalaa]

(Original post by grazie)
I think whoever teaches you maths hasn't given you precise descriptions of the terms you've 1.2342452.., 2.333333333333333.., 2.1718281.., 3.142.., 1.13 (to 3sf for 1.125 exact value), etc.

... err.. ye maybee! thankss!

[Arva]

(Original post by TheNoobyPotato)
So if its above 90 but below 180, you would do 180 - Ans. If it was above 270, you would do 360 - ...

Right?

Please ignore the advice I gave on vectors yesterday, it was all wrong, I'm really sorry.

[Arva]

(Original post by grazie)
Arva ->

OK, I'm back.

[grazie]

(Original post by Lalaa)
... err.. ye maybee! thankss!

You're welcome.

I think a lot of confusion arises because a rationalised surd is in a fact an irrational number. It's a bit of a misnomer, but I don't want to confuse you

[JuxtaposedJames]

Whats the grade boundaries usually like in C4??

[Arva]

(Original post by JuxtaposedJames)
Whats the grade boundaries usually like in C4??

Someone posted a list of all the grade boundaries yesterday, it should be a couple of pages back.

[Lalaa]

(Original post by grazie)
You're welcome.

I think a lot of confusion arises because a rationalised surd is in a fact an irrational number. It's a bit of a misnomer, but I don't want to confuse you

noo you havent confused mee.. i think i was just confused.. sort out now though! thanks!

[TheNoobyPotato]

(Original post by Arva)
Please ignore the advice I gave on vectors yesterday, it was all wrong, I'm really sorry.

Okay, that's fine

This was posted from The Student Room's Android App on my GT-S5830

[TheNoobyPotato]

(Original post by Llewellyn)
You're doing a cosine function. The angle you find will never be greater than 180 degrees. There's no point in trying to overcomplicate the scalar product. There is one angle which you will get by simply using the inverse cosine function.

There cannot be multiple angles for vectors. Remember, vectors have direction so there is only one angle that is made between them. Don't get vectors confused with Cartesian equations.

Okay Thanks!

This was posted from The Student Room's Android App on my GT-S5830

[Jack_Smith]

Just did specimen paper and it wasn't as hard as you expect specimen papers to be!=D Oh i wish c4 turns out like the specimen!!

[sceptic_medic]

(Original post by JuxtaposedJames)
Whats the grade boundaries usually like in C4??

Average has been around 60 for an A, though they have been higher in recent years.

[JordanS94]

(Original post by marc_h94)
Average has been around 60 for an A, though they have been higher in recent years.

I think it will be around 60/61 this time because the last one was considered easy, you needed 65 for an A.

[Arva]

Oh god I'm crap at differential equations... Trying to go through all the ones in the textbook but when I get one wrong there's no worked solution so all I can do is try it again. I think I'm going to start doing papers instead now.