[Kravez]

Do you have to learn the sin/cos/tan graphs aswell as the unit circle? Or one of the two because we've only been taught the unit circle method and apparently knowing the sin/tan/cos graphs aren't needed.

I'm just making sure as I don't have much faith in my teacher.

[JohnyTheLad]

Can I ask what is this "unit circle" that you speak of? and for which board?

[dslc]

If you're referring to what is also known as the CAST method, it is usually down to preference.
However, you must know the graphs in instances where the result lands on 90 degrees as CAST cannot be used here.

So really, in answer, both.

[Intriguing Alias]

(Original post by dslc)
If you're referring to what is also known as the CAST method, it is usually down to preference.
However, you must know the graphs in instances where the result lands on 90 degrees as CAST cannot be used here.

So really, in answer, both.

Or avoid needing to know both and just know the graphs

The 90 degree marks are fairly simple to just 'know', OP, so using CAST is probably fine. I personally much prefer learning the graphs (and it's helped me in situations where I've needed to sketch transformations of sin/cos/tan graphs in STEP ).

[dslc]

(Original post by hassi94)
Or avoid needing to know both and just know the graphs

The 90 degree marks are fairly simple to just 'know', OP, so using CAST is probably fine. I personally much prefer learning the graphs (and it's helped me in situations where I've needed to sketch transformations of sin/cos/tan graphs in STEP ).

This is true!

Though, judging by your mention of STEP papers it's clear you aren't exactly mathematically challenged
I'd say the CAST method is a beneficial addition to a student's maths toolkit when they perhaps struggle a little with trig functions

[TenOfThem]

(Original post by dslc)
If you're referring to what is also known as the CAST method, it is usually down to preference.
However, you must know the graphs in instances where the result lands on 90 degrees as CAST cannot be used here.

So really, in answer, both.

Of course CAST can be used at 90

[TenOfThem]

(Original post by hassi94)
Or avoid needing to know both and just know the graphs

Or avoid needing to know 3 different graphs and just know CAST

[Intriguing Alias]

(Original post by TenOfThem)
Or avoid needing to know 3 different graphs and just know CAST

Well that was just in response to the person saying to know both because CAST doesn't work at 90 degrees (no idea if this is true, mind you - I don't know what CAST is really).

I did later in my post say I'm sure CAST is fine to use so the OP should be fine. And then said personally I prefer knowing the graphs anyway

[TenOfThem]

(Original post by hassi94)
Well that was just in response to the person saying to know both because CAST doesn't work at 90 degrees (no idea if this is true, mind you - I don't know what CAST is really).

I did later in my post say I'm sure CAST is fine to use so the OP should be fine. And then said personally I prefer knowing the graphs anyway

Just teasing

I am a CAST fan ... anything for an easy life that requires me to learn/remember the absolute minimum

[dslc]

(Original post by TenOfThem)
Of course CAST can be used at 90

With a principal value of 90 degrees, how do you use the CAST diagram?

[TenOfThem]

(Original post by dslc)
With a principal value of 90 degrees, how do you use the CAST diagram?

In the same way that you use it for any other angle

[dslc]

(Original post by TenOfThem)
In the same way that you use it for any other angle

Usually you'd find my principal value and put that onto my CAST diagram. Then you'd find the other values using the C(os+)-A(ll+)-S(in+)-T(an+). If the principal angle was 90 degrees, how would you know where else to find the other points? You'd be in-between regions

It's hard to explain in words why it doesn't work - but I was taught it doesn't?

[TenOfThem]

It is the meeting point of Q1 and Q2