ATAR Notes: Forum

VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Mathematical Methods CAS => Topic started by: chuckjefster90 on October 08, 2009, 06:29:21 pm

Title: Modulas
Post by: chuckjefster90 on October 08, 2009, 06:29:21 pm

How do u find relevant intervals and solve abs(x^2-4)-5 alebraically?

Title: Re: Modulas
Post by: Flaming_Arrow on October 08, 2009, 06:32:37 pm

|x^2-4|=5

x^2-4=5 and x^2-4=-5
x^2-9 and x^2+1=0

x= +-3 

Title: Re: Modulas
Post by: chuckjefster90 on October 08, 2009, 06:40:40 pm

THNX

Title: Re: Modulas
Post by: TrueTears on October 08, 2009, 09:54:29 pm

Quote from: Flaming_Arrow on October 08, 2009, 06:32:37 pm

|x^2-4|=5

x^2-4=5 and x^2-4=-5
x^2-9 and x^2+1=0

x= +-3 

But also be careful to remember the domain for each hybrid function :P

Title: Re: Modulas
Post by: kamil9876 on October 08, 2009, 10:05:40 pm

^ he didn't do it like that. A very good and quick way, no need to worry about domain, that would be a round about way.

Title: Re: Modulas
Post by: TrueTears on October 08, 2009, 10:06:21 pm

Quote from: kamil9876 on October 08, 2009, 10:05:40 pm

^ he didn't do it like that. A very good and quick way, no need to worry about domain, that would be a round about way.

I know but didn't OP said "find relevant intervals"

Title: Re: Modulas
Post by: kamil9876 on October 08, 2009, 10:07:19 pm

oh yeah lol i just focused on the reply and it looked like he was solving