Parametrics (1 Viewer)

Bdogz

Member
Joined
May 7, 2008
Messages
152
Gender
Male
HSC
N/A
<HR style="BACKGROUND-COLOR: #d1d1e1; COLOR: #d1d1e1" SIZE=1>
<!-- google_ad_section_start -->When it says determine the cartesian equation of the locus etc.. is it ok if u just leave it as say x^2=4ay or do u hv to say with vertex (0,0) and focus (0,a)

Example: show that T is constrained to move on a parabola,
the answer becomes x^2=4 * a/2(y+a) then the answer sed: this is the equation of a parabola, with vertex (0,-a) and focus (0, -a/2)

Will you get full marks if u jsut rite x^2=4 * a/2(y+a)?

thnks
 

emmcyclopedia

Member
Joined
Oct 7, 2008
Messages
391
Gender
Female
HSC
2009
No - I'm pretty sure you have to also state the vertex and focus.
We had a question like this in our trials and some people lost a mark for not mentioning them, even though the question didn't explicitly state that you had to show these co-ordinates.
Either way, it's only one line, and it doesn't hurt to put it in there =]
 

Bdogz

Member
Joined
May 7, 2008
Messages
152
Gender
Male
HSC
N/A
No - I'm pretty sure you have to also state the vertex and focus.
We had a question like this in our trials and some people lost a mark for not mentioning them, even though the question didn't explicitly state that you had to show these co-ordinates.
Either way, it's only one line, and it doesn't hurt to put it in there =]
oh k, thnx 4 letting me know:)
 

Aquawhite

Retiring
Joined
Jul 14, 2008
Messages
4,946
Location
Gold Coast
Gender
Male
HSC
2010
Uni Grad
2013
Tough one. I'll ask my teacher tomorrow (going into school tomorrow :))
 

kwabon

Banned
Joined
May 26, 2008
Messages
646
Location
right behind you, mate
Gender
Male
HSC
2009
<hr style="background-color: rgb(209, 209, 225); color: rgb(209, 209, 225);" size="1">
<!-- google_ad_section_start -->When it says determine the cartesian equation of the locus etc.. is it ok if u just leave it as say x^2=4ay or do u hv to say with vertex (0,0) and focus (0,a)

Example: show that T is constrained to move on a parabola,
the answer becomes x^2=4 * a/2(y+a) then the answer sed: this is the equation of a parabola, with vertex (0,-a) and focus (0, -a/2)

Will you get full marks if u jsut rite x^2=4 * a/2(y+a)?

thnks
you will get full marks,

unless it asks for specifics, such as, "mention important points of the locus", only then ramble about the vertex and focus and what not.
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top