Radians/Degrees (1 Viewer)

davidbarnes

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Converting radians to degrees and vice versa confuses me. I can sort of do it, althogh not really the way we're supposed to.

Something like
pie over 12 = 1 rad
pie over 6 = 2? rad

I have no idea really. So whats the deal with pie over 12, pie over 6 etc. What comes next, pie over 3???
 

jb_nc

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1 radian = 180 degrees.

you times degrees by pi/180 and radians by 180/pi to get radians and degrees respectivley.
 

davidbarnes

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I thoguht 1 radian equalled 15 degrees, and that therer was 24 radians in a 360 degree circle.
 

davidbarnes

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Thanks. I actually have already downloaded those before and have them already. Never thought of checking them.
 

ellen.louise

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davidbarnes said:
I thoguht 1 radian equalled 15 degrees, and that therer was 24 radians in a 360 degree circle.
nope. more like 52 degrees! there are 2 pi radians in 360 degrees.

pi radians = 180 degrees so pi/3 radians is 60 degrees, pi/2 radians is 90 degrees, etc.
 

Slidey

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You also need to know the exact ratios inside out.
 

davidbarnes

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Exphate said:
pi/3, pi/4 pi/2 pi/6

you need to know these inside and out

pi/2 = 90
pi/4 = 45

pi/3 = 60
pi/6 = 30

Pi = 180 degrees.

There, you need to know pi, now you can convert into any rads.
Ok I understand that. Althoguh how does one convert to Radians then?
 

Bank$

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davidbarnes said:
Ok I understand that. Althoguh how does one convert to Radians then?
Pie radiens = 180 degree

so then u manipulate that relationship to say

1 radien = (180 degree/pie)
or
1 degree = Pie radiens/180

so say u want to convert 135 degree:

u divide 135 by 180 then multiply by pie and u will have changed it to radiens:

(135/180)pie radiens = 135 degree
 

aussiechica7

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remember if u divide something by itself, it is one, right?
so 50, 000 divided by 50, 000 = 1.


also remember, if you multiply something by one, it's the same, right?
so like 1, 000, 000 times 1 = 1, 000, 000.


ok trust me when i say pi radians equals 180 degrees, ok?

so pi radians divided by 180 degrees = 1
and
180 degrees divided by pi radians = 1

correct?

so all you have to do is multiply whatever you have by 1. you won't express 1 as "1" you might express it as 180 degrees divided by pi radians or pi radians divided by 180 degrees.

so you have "pi/3" radians. to make it degrees, multiply it by 180 degrees/pi radians. this will allow you to cancel the radians out (and the pi, usually).

pi/3 radians x 180 degrees/ pi radians = 60 degrees.

how about if you have say 45 degrees? multiple by "one" so that you can cancel the degrees out. we said before pi radians/180 degrees = 1.

so,

45 degrees x pi radians/180 degrees = (pi/4) radians
 

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