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VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Mathematical Methods CAS => Topic started by: wildareal on September 27, 2010, 12:58:16 pm

Title: How do you do General Solutions?
Post by: wildareal on September 27, 2010, 12:58:16 pm: I usually get the two reference angles + or - period. eg sin(x)=1/2

x= TT/6, 5TT/6

then:

x=2nTT+-TT/6 and x=2TTn+-5TT/6
Title: Re: How do you do General Solutions?
Post by: vea on September 27, 2010, 01:37:57 pm: That's the way I do it too but if you look at TT's stickied thread, it shows you the more conceptual way of doing it.

Have you been taught general solutions at school or are you reading ahead? We were never taught it last year in 1/2...
Title: Re: How do you do General Solutions?
Post by: Jdog on September 27, 2010, 01:48:35 pm: theres just 3 formulas you rember they make a lot of sense as well, so you don't have to spend ages memorizing them,
Title: Re: How do you do General Solutions?
Post by: letsride on September 27, 2010, 01:57:21 pm: you forgot the n element of Z

that lil error can cost you a mark =P
Title: Re: How do you do General Solutions?
Post by: naved_s9994 on September 27, 2010, 05:25:53 pm: Quote from: cherylim23 on September 27, 2010, 05:15:19 pm
...I'm a bit confused.

Isn't the plus/minus sign included in the element of Z? (I use element of J however.)

Also, is it necessary to state that n is an element of Z? I don't do it in my outcomes (and my teacher doesn't either :P).

Z is an integer, and indicated ...-2,-1,0,1,2...
Typically books / VCAA/ Trial Exams solutions have n as an element of Z.
Title: Re: How do you do General Solutions?
Post by: wildareal on September 27, 2010, 05:45:58 pm: Quote from: naved_s9994 on September 27, 2010, 05:25:53 pm
Quote from: cherylim23 on September 27, 2010, 05:15:19 pm
...I'm a bit confused.

Isn't the plus/minus sign included in the element of Z? (I use element of J however.)

Also, is it necessary to state that n is an element of Z? I don't do it in my outcomes (and my teacher doesn't either :P).

Yer most use Z, some use N.

Z is an integer, and indicated ...-2,-1,0,1,2...
Typically books / VCAA/ Trial Exams solutions have n as an element of Z.
Title: Re: How do you do General Solutions?
Post by: m@tty on September 27, 2010, 06:38:47 pm: You DO need to specify what $n$ is. If you don't, then what are the examiner's meant to do? Assume you know what you are doing?

Also, you don't need $\pm n, n\in \mathbb{Z}$ , because Z already covers negatives.