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# Parametric to cartesian C4 watch

1. Hi
I am not really having good time with the conversion, i know if the parameter is theta trig. idenetities need to be used , but i dont know where to begin from. Question is:Find x^2/3 in terms of theta.
x= cos^3 (theta) and y= sin^3 (theta)
at first i thought of cubing x side and squaring it , to get x ^2/3 = cos^2 theta) and then let theta= x^(2/3) /cos. to sub into y =/.
Thanks.
2. (Original post by ibysaiyan)
x^(2/3) /cos
What does this mean?!

If x^(2/3) = cos^2 theta, then 1 - x^(2/3) = sin^2 theta, so...
3. (Original post by generalebriety)
What does this mean?!

If x^(2/3) = cos^2 theta, then 1 - x^(2/3) = sin^2 theta, so...
Sorry but i still don't get it, i see you have used sin^2+cos^1 = 1 .So.. now what?I thought of subbing in theta value into y.
4. (Original post by ibysaiyan)
Sorry but i still don't get it, i see you have used sin^2+cos^1 = 1 .So.. now what?I thought of subbing in theta value into y.
We have sin^2 theta in terms of x. And we have sin^3 theta in terms of y. How can we relate these two? (Hint: try and write sin^2 theta in terms of y, in the same way you wrote cos^2 theta in terms of x.)

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