Vector parameterization of intersection of 2 surfaces

musicmar
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Homework Statement


Find a vector parameterization of the intersection of the surfaces x2+y4+2z3=6 and x=y2 in R3.


The Attempt at a Solution



I let x=t.
Then y3=t

I solved the first equation for z in terms of x
z = cube root ((t2+(t(cube rt(t)) - 6)/-2)

I know this is wrong because I checked the back of the book, but I'm not sure how to do it correctly.
Thank you!
 
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musicmar said:
I let x=t.
Then y3=t

Is your 2nd surface x=y^2 or x=y^3?

In either case, to avoid taking sqare roots and cube roots of stuff, try letting y=t instead and solving for x.
 
x=y3, sorry.

So, when y=t, x=t3
and z= cube rt ((-1/2)(t6+t4-6))

This is still wrong. The answer is <t2,t,cube rt(3-t4)>
It doesn't help that I know the answer unless I know how to do it, though.
 
musicmar said:
x=y3, sorry.

So, when y=t, x=t3
and z= cube rt ((-1/2)(t6+t4-6))

This is still wrong. The answer is <t2,t,cube rt(3-t4)>
It doesn't help that I know the answer unless I know how to do it, though.

Judging from the answer, it looks as though the 2nd surface is supposed to be x=y^2, so I'd double check the question if I were you.
 
thank you. you were right, it was x=y^2.
 
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