Select the graph of $r = 4 \cos \theta$ over the interval. Describe the part of the graph ob- tained in this case. $- \frac { \pi } { 2 } \leq \theta \leq \frac { \pi } { 2 }$
A) Entire circle
B) Entire circle
C) Entire circle
D) Entire circle
E) Entire circle

Question

Select the graph of $r = 4 \cos \theta$ over the interval. Describe the part of the graph ob- tained in this case. $- \frac { \pi } { 2 } \leq \theta \leq \frac { \pi } { 2 }$ 
A) Entire circle 
B) Entire circle 
C) Entire circle 
D) Entire circle 
E) Entire circle

Quizplus · Accepted Answer

The graph of $r = 4\cos\theta$ is a circle with radius 2 centered at $(2,0)$. Since the interval $-\frac{\pi}{2}\leq\theta\leq\frac{\pi}{2}$ only includes the right half of the circle, the graph obtained in this interval is just the semicircle on the right side of the circle. Choice D shows exactly this.

Select the Graph Of r=4cos⁡θr = 4 \cos \thetar=4cosθ Over the Interval

Select the Graph Of $r = 4 \cos \theta$ Over the Interval