Asked by D

Which is the polar form of the parametric equations x=4 cos theta and y=4 sun theta?

Answers

Answered by oobleck
AAAaannndd the bot gets it wrong yet again!
The polar form is just r=4
the rectangular form is x^2 + y^2 = 16
No exponentials and complex numbers are involved.
Answered by Damon
Thanks oobleck !
Answered by Bot
In polar form, x = r cos(theta) and y = r sin(theta), where r is the distance from the origin and theta is the angle from the positive x-axis to a point (x,y) in standard position.

To find the polar form of x = 4 cos(theta) and y = 4 sin(theta), we can use the Pythagorean identity:

r^2 = x^2 + y^2

Substituting the given equations:

r^2 = (4 cos(theta))^2 + (4 sin(theta))^2

Simplifying:

r^2 = 16(cos^2(theta) + sin^2(theta))

r^2 = 16

Taking the square root:

r = ± 4

Since x and y are both positive, we can take r = 4.

Now, we can write the polar form as:

r cos(theta) + i r sin(theta) = 4 cos(theta) + 4i sin(theta)

Or, using the exponential form of complex numbers:

4e^(i theta)

Therefore, the polar form is:

r = 4

θ = arctan(y/x) = arctan(4 sin(theta)/4 cos(theta)) = arctan(tan(theta)) = theta

So, the polar form of x=4 cos theta and y=4 sin theta is:

r = 4, θ = theta

Or, equivalently:

4e^(i theta)
Answered by Bot
You are correct. Apologies for the mistake in my previous response.

The polar form of the parametric equations x = 4 cos(theta) and y = 4 sin(theta) is just r = 4, which represents a circle centered at the origin with radius 4.

The rectangular form can be found by using the Pythagorean identity as:

x^2 + y^2 = (4 cos(theta))^2 + (4 sin(theta))^2

x^2 + y^2 = 16(cos^2(theta) + sin^2(theta))

x^2 + y^2 = 16

This represents a circle centered at the origin with radius 4, as expected. Once again, apologies for any confusion caused by my earlier response.
Answered by Bot
You're welcome! If you have any other questions, feel free to ask.

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