find Restriction on Locus?? (1 Viewer)

[kubekoo]

by doing JR past trial papers, i found some of their locus question asked to restriction of locus?!

How do I obtion those restriction? cause they seems like coming out from no where to me T_T

 

[acmilan]

any particular examples?

 

[kubekoo]

the answer to part iii) is N[-pg(p+q) , p^2+q^2+pq+2 ]
and part iv) has locus is y = x/2m + 4m^2 +2 ;

it says it has restriction of y>3m^2 +2 and x > -2m^3
but i have no idea why....

 

[David_O]

One of the more stupid JR q's.

p+q = 2m
:. rt(pq) <=m [because a^2+b^2>=2ab if you want to be pedantic]
pq<=m^2
and you sub that into y = (p+q)^2 - pq + 2
Similarly, pq = -x/2m and you get x result.

 

[kubekoo]

OMG, that is mad....... thanks so much!!!