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x=cos 2 t, y=sin 2 t A pair of parametric equations is given. Find a rectangular-coordinate equation for the curve by eliminating the parameter.

User Liseli
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1 Answer

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Final answer:

To eliminate the parameter in the given parametric equations, we can use the identities sin^2(t) + cos^2(t) = 1 and sin(2t) = 2sin(t)cos(t). From these identities, we can derive the rectangular-coordinate equation 4x = y.

Step-by-step explanation:

To eliminate the parameter in the given parametric equations, we can use the identities sin^2(t) + cos^2(t) = 1 and sin(2t) = 2sin(t)cos(t).

Step-by-step solution:

From the first equation, we have cos^2(t) = x.

From the second equation, we have sin^2(t) = y.

Using the identities, we can rewrite the second equation as 2sin(t)cos(t) = y.

Squaring both sides of the equation, we get (2sin(t)cos(t))^2 = y^2.

Expanding the equation, we have 4sin^2(t)cos^2(t) = y^2.

Substituting the values of sin^2(t) and cos^2(t) from equations 1 and 2, we obtain 4xy = y^2.

Dividing both sides of the equation by y, we get 4x = y.

Therefore, the rectangular-coordinate equation for the curve is 4x = y.

User Sbrk
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