# Lesson goal: Sin, cos and circles

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You can use a for-loop and sin and cos to investigate how circles are formed. Remember that in the unit circle, the $x$ coordinate is always represented by $\cos$ and the $y$ by the $\sin$. So suppose you used a for-loop to count from $0$ to $360^\circ$. Using this angle to compute both the sin and cos, could you use pset to plot a circle?

This is a good time to experiment with the step parameter with for loops. Review this parameter here in case you forgot.

# Now you try. Try fixing the for angle= statement.

Type your code here:

See your results here:

This code will not run. You have to fix two things. First, the radius= line. What radius to you want your circle to be? Next, the for angle= statement to run through the angles over which a circle exists. What do you think these fixes will be? Can you do it? Dismiss.
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