Valerie Russell
Assignment 11
Polar Equations
when a > 0:
The circle increases as a increases above the xaxis. The circle increases as a increases to the right of the xaxis.
when a < 0:
The circle increases as a increases below the xaxis. The circle increases as a inreases to the left of the xaxis.
Whether sine or cosine a represents the the diameter of the circle.
Let's investigate the polar equation for different values of n:
Petals on a Rose with Cosine When n is 1,the graph looks like a heart as in the first polar equation. When n is 2, the graph has 2 petals. When n is 4, the graph has 4 petals. As n increases, the number of petals on the rose increases. 
Petals on a Rose with Sine Notice that changing the function from Cosine to Sine only changes the rotation. The picture remains the same 
Values of a Notice that changing the coefficient of a expands the polar equation. A coefficient of 2 expands the petals to 2 and a coefficient of 3 expands the petals to 3 and so on... Can you guess what n is in each equation? Hint: Remember to count the number of petals in the rose. 

Values of b: Notice the Cosine and Sine functions are going in opposite directions. As b increases, the functions stretch horizontally and vertically. 
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