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C4 differentiation parametric equations

x=2cot t
y= 2 sin^2 t

Find a caresian equation of the curve in the form y=f(x)

please can somebody help me do this? never come across this kind of equation before?

Reply 1

TenOfThem

Original post by Hellospaceboyy

x=2cot t
y= 2 sin^2 t

Find a caresian equation of the curve in the form y=f(x)

please can somebody help me do this? never come across this kind of equation before?

Square x

Write it in terms of Sinx

Reply 2

Hellospaceboyy

Original post by TenOfThem

Square x

Write it in terms of Sinx

please could you explain a bit more? i'm still confused

Reply 3

Gaiaphage

cot(t) = x/2
tan(t) = 2/x
sin(t) = 2cos(t)/x
sin^2(t) = 4cos^2(t)/x^2

Also from the other equation:
sin^2(t) = y/2

So, y/2 = 4cos^2(t)/x^2
y = 8cos^2(t)/x^2

Reply 4

TenOfThem