- #1
chwala
Gold Member
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- Homework Statement
- This is a past paper question...see attached (my interest is on the highlighted) I used a different approach thus your insight would be great. I always make it a point to try out the questions before checking what the mark scheme offers...
- Relevant Equations
- parametric equations.
Find ms solution;
My approach;
##xt=t^2+2## and ##yt=t^2-2##
##xt-2=t^2## and ##yt+2=t^2##
##⇒xt-2=yt+2##
##xt-yt=4##
##t(x-y)=4##
##t=\dfrac{4}{x-y}##
We know that;
##x+y=2t##
##x+y=2⋅\dfrac{4}{x-y}##
##(x-y)(x+y)=8##
##x^2-y^2=8##
Your insight is welcome...rather asking if this approach would be correct.