# Question #5b70d

##### 2 Answers

#### Explanation:

This is the unit circle about the Origin

- Take the parameterisation in polar coordinates:

- Observe that:

- Then note that you actually have:

I'd go with the

.

#### Explanation:

To convert from

#color(blue)"cartesian to polar form"#

#color(red)(bar(ul(|color(white)(2/2)color(black)(x=rcostheta;y=rsintheta)color(white)(2/2)|)))#

#x^2+y^2=1#

#rArr(rcostheta)^2+(rsintheta)^2=1#

#rArrr^2cos^2theta+r^2sin^2theta=1#

#rArrr^2(cos^2theta+sin^2theta)=1#

#rArrr^2=1" since "cos^2theta+sin^2theta=1# This is the equation of a circle, centred at the origin with radius 1