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whe do u use radians instead of degrees?

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Reply 20

tiny hobbit

ukdragon37

Always.

Not a good plan if you have an exam question that asks for answers in degrees!

Reply 21

didgeridoo12uk

phen

I'm not sure I know what you mean. o__o

as in when you are differentiating a function, and you come to evaluate it at lets say x=5

you always take that to mean 5 radians, not 5 degrees, when putting it into a trigonometric function

Reply 22

phen

didgeridoo12uk

as in when you are differentiating a function, and you come to evaluate it at lets say x=5

you always take that to mean 5 radians, not 5 degrees, when putting it into a trigonometric function

Ahh, like that. I see you added the last bit in between my time of reading your post and pressing the 'quote' button. :P

Reply 23

didgeridoo12uk

phen

Ahh, like that. I see you added the last bit in between my time of reading your post and pressing the 'quote' button. :P

lol i always end up editing my posts 3 or 4 times

but yeh before i realised that, i would constantly get the answers wrong in questions and just not be able to work out what on earth i was doing wrong!

Reply 24

ukdragon37

tiny hobbit

Not a good plan if you have an exam question that asks for answers in degrees!

As I said, use degrees if you must. However once you are in university you can be be 99% certain there will be no questions involving degrees. You'll need to get used to radians one day.

Reply 25

generalebriety

nuodai

I've not used degrees since starting uni.

One of my lecturers used degrees. I stopped attending his lectures out of embarrassment for him.

ukdragon37

As I said, use degrees if you must.

I really don't recommend it, since you'll get all calculus questions involving trig functions wrong.

Reply 26

Good Apollo

SirMasterKey

If in an exam paper just look for the super script. An o means degrees, an r means radians.

Most other stuff regarding radians as already been said.

It's a superscript "c" for radians, actually.

In response to the OP, always use radians unless told otherwise. As a general rule of thumb, questions given in terms of pi will always need you to use radians, and questions given to you in whole numbers will often need to be solved in degrees (especially if they're the typical "degree numbers", e.g. 90, 180, etc.).

Reply 27

phen

didgeridoo12uk

If I get a question like the one you're talking about, I usually get them with x=2pi or x=pi or x=1/12 pi or stuff in that order. It makes it pretty obvious they want radians and not degrees.

In all fairness, I edited that post in which I quoted you like 3 times cause I kept messing up. XD At first, I quoted myself on accident (cause you had the quote tags with my name in your post) and didn't properly fix it until after like 3 times.

Reply 28

phen

generalebriety

I really don't recommend it, since you'll get all calculus questions involving trig functions wrong.

'when you must' = when the assignment states you must give an answer in degrees.

Reply 29

ukdragon37

generalebriety

I really don't recommend it, since you'll get all calculus questions involving trig functions wrong.

What I meant is that if the question actually says "express in degrees" then use degrees, otherwise use radians always. :p:

Reply 30

generalebriety

phen

'when you must' = when the assignment states you must give an answer in degrees.

He said "if you must", which sounds like it means something completely different (e.g. "if you insist[noparse]")[/noparse]. But he has since clarified, so all is well.

Reply 31

Kolya

RightSaidJames

Degrees are an invention to make pre-A-Level Maths more simple to understand.

No they aren't :no:

Degrees have been around for much longer than radians.

Reply 32

xSkyFire

The nerd level of this thread just broke 9000 :p:

Reply 33

vahik92

at A level it will almost always be clear what to use. you will usually get at least one other angle if you are asked to find an angle, and if not, use whatever you like - i dont see neither an embarasment nor something wrong with degrees as others say as Ive never got a single answer wrong with using degrees unless radians specified. I have finished all core mathematics units and FP1 and the only place that requires to use radians is when finding a length or something of a circle sector - but that can be done by degrees as well if you convert them into radians - it still works !

in other words, from as far as i have seen, there hasnt been a single situation where one would work and the other wont, maybe at uni some things dont work, but at A level I havent seen anything like that.

Reply 34

vahik92

perhaps, a better asnwer would be - do NOT use degrees as radians and the opposite (e.g. sin5 in degrees isnt the same as sin5 in radians.). in other cases, from as far as I know you will still get the right answer.

Reply 35

Fatal_Microbes

Ignore All Above Posts

The only real reason we use radians is to try to talk to aliens because they wouldn't understand the concept of degrees.

Not infact to benefit the gcse student who wouldn't understand radians

Reply 36

vahik92

ukdragon37

What I meant is that if the question actually says "express in degrees" then use degrees, otherwise use radians always. :p:

i dont always use radians, i dont really like them, degrees for me is much simpler. its not easier as they are almost the same, but because i have been using degrees for about 7-8 years now, its as simple as the multiplication table. btw i have never done a single mistake working with degrees where the mistake wouldn't happen if i used radians , so id say use whatever you prefer - unless of course the problem isnt solvable with degrees which as i said ive never come across.

Reply 37

generalebriety

vahik92

unless of course the problem isnt solvable with degrees which as i said ive never come across.

Again, anything involving calculus with trigonometric functions... :confused:

Reply 38

ukdragon37

vahik92

in other words, from as far as i have seen, there hasnt been a single situation where one would work and the other wont, maybe at uni some things dont work, but at A level I havent seen anything like that.

Haven't you done trigonometric differentiation/integration? You try integrate a term containing a trigonometric function with degree limits.

Reply 39

vahik92

ukdragon37

Haven't you done trigonometric differentiation/integration? You try integrate a term containing a trigonometric function with degree limits.

erm..if you convert them you still can do it cant you?
e.g. if the question asks to find for example a sin of a right angle, you can use both right? sin pi/2 = sin 90. even if it says for example 2p radians, you can use 360 degrees cant you?

still correct isnt it?