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c4 parameshits

need help the markscheme doesnt help

The curve C has parametric equations

x=1/(t+1)
y=1/(1-t)

show that C satisfies the cartesian equation y = x/(2x-1)
you may need to edit the thread title :h:
Rearrange the first equation to find a value of t in terms of x and then plug that in to the t in the y equation.
Reply 3
Rearrange the equation with x to make t the subject then sub it into the second equation.
Love the thread title lol
Original post by HateOCR
Rearrange the equation with x to make t the subject then sub it into the second equation.
Love the thread title lol


a did mate, here let me show you

x=1/(1+t)
t=(1/x) -1

sub t into y

y= 1/(1-1/x)

which i get as -x/1 = -x
Reply 5
I got
Original post by awijdijwajiodji
a did mate, here let me show you

x=1/(1 t)
t=(1/x) -1

sub t into y

y= 1/(1-1/x)

which i get as -x/1 = -x


I got y=1/(2-1/x)
You can factorise 2x-1 so you get
Y=1/1/x(2x-1)
1/1/x is the same as x so
Y=x/(2x-1)

You didnt sub it back in correctly
(edited 6 years ago)
Reply 6
Here sorry for the scrunched up paper i threw it after i solved it lol
B7A530F2-3E14-4F5B-967B-A8E151DBC0C6.jpg.jpeg
Original post by HateOCR
Here sorry for the scrunched up paper i threw it after i solved it lol
B7A530F2-3E14-4F5B-967B-A8E151DBC0C6.jpg.jpeg


on the 6th line idk why you took out 2x-1 how do you know how to do that?
Reply 8
Original post by awijdijwajiodji
on the 6th line idk why you took out 2x-1 how do you know how to do that?


Because the question says it was 2x-1 in the denominator. Also if you try expanding the bracket you will see you end up with 2-1/x therefore it works.

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