Trigonometric functions (1 Viewer)

Winston

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Hey guys i just started on this topic and im totally lost
coz the teacher is a bit confusing

do u have to remmeber all those

pi/2, 3pi/4 etc... values off by heart or is there another way of remembering it
 

kini mini

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Hi Winston

I didn't actually do 2U, I did 4U, but I'm moonlighting :D

What aspect of radians do you find confusing? All you have to remember is that 2 pi radians are equivalent to 360 degrees. With the number of practice questions you'll do, you'll be able to think in radians just as you think in degrees now :).
 

Minai

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Yep, practice makes perfect - the more u do, the more familliar u'll get with the whole radians vs degrees (eg noticing patterns etc)
If ur still stuck, use ur calculator - jus know how to correctly convert
 

CHUDYMASTER

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The more correct way to look at it is that pi is a numerical value that corresponds to 180 degrees. This is important because degrees don't exist on our numbering system and hence you cannot use the numerical values of degrees/minutes/seconds to work out critical lengths such as that of a circle or the area of a segment.

Basically, 1 pi (which is referred to as radian measure) is the result of dividing the circumference of a semi circle by its radius length (hence the term radian measure). This is why 1 pi rad is equated to 180 degrees (because there are 180 degrees from the first quadrant to the second in a semi circle)

And once you have this value pi (3.142 etc..), you use it as a standard for finding other values.
eg.
if 1 pi radians = 180 degrees
then 2 pi radians must be twice the size of 1 pi radians, which is 360 degrees.

so if you get something like n degrees which you want to convert into radian measure, you say: x = n/180*pi

Simple? I thought so.
 
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Winston

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but ok this is what we are up to
i do get radians
but the other period she gave us gfx calculators to look at graphs and like there was a question sayin

what are the values of the maximum, minimum, zero

and we had a little table as follows


pi/2 = 1.6
pi/3 = wateva
etc..


and then wen we moved the point to the maximum of the graph

we had to state wats the pi over wat

say the maxium had been 1.5669...

then we look at which one is the closes
so in this case pi/2 was 1.6 so therefore the maximum is pi/2


wat imasking is

do i have to remember all this pi over sumfing values etc etc..

or is there a pattern or method to remember it
 

McLake

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Originally posted by Winston
wat imasking is

do i have to remember all this pi over sumfing values etc etc..

or is there a pattern or method to remember it
I'm not familiar with the format of the 2U test, but I am pretty sure you have a calculator. Just switch your clalculator to "radian" mode and calculate the values if you need them ...
 

kini mini

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Originally posted by McLake


I'm not familiar with the format of the 2U test, but I am pretty sure you have a calculator. Just switch your clalculator to "radian" mode and calculate the values if you need them ...
I agree, I can't see them asking you to remember that.
 

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