Find the best solutions to your problems with the help of IDNLearn.com. Ask your questions and receive detailed and reliable answers from our experienced and knowledgeable community members.

What is the maximum [tex]\( r \)[/tex]-value for the polar equation [tex]\( r = -3 + 5 \sin \theta \)[/tex]?

Note that a maximum [tex]\( r \)[/tex]-value is a maximum value of [tex]\(|r|\)[/tex], the maximum distance from the pole.

A. 8
B. 5
C. 2
D. 3

Please select the best answer from the choices provided:
A
B
C
D


Sagot :

To find the maximum [tex]\( r \)[/tex]-value for the polar equation [tex]\( r = -3 + 5 \sin \theta \)[/tex], we need to analyze the behavior of the function.

1. Understand the equation: The given polar equation is [tex]\( r = -3 + 5 \sin \theta \)[/tex]. Here, [tex]\( \theta \)[/tex] is the variable that affects the value of [tex]\( \sin \theta \)[/tex].

2. Range of sine function: The sine function, [tex]\( \sin \theta \)[/tex], oscillates between -1 and 1 for all values of [tex]\( \theta \)[/tex]. This means:
[tex]\[ -1 \leq \sin \theta \leq 1 \][/tex]

3. Determine the extreme values for [tex]\( r \)[/tex]:
- When [tex]\( \sin \theta \)[/tex] is at its minimum value, [tex]\(-1\)[/tex]:
[tex]\[ r = -3 + 5(-1) = -3 - 5 = -8 \][/tex]
- When [tex]\( \sin \theta \)[/tex] is at its maximum value, [tex]\(1\)[/tex]:
[tex]\[ r = -3 + 5(1) = -3 + 5 = 2 \][/tex]

4. Finding the maximum [tex]\( r \)[/tex]-value:
We need to find the maximum value of [tex]\( r = -3 + 5 \sin \theta \)[/tex]. From the calculations in step 3:
- The minimum value of [tex]\( r \)[/tex] is [tex]\(-8\)[/tex]
- The maximum value of [tex]\( r \)[/tex] is [tex]\( 2 \)[/tex]

5. Conclusion:
The maximum [tex]\( r \)[/tex]-value for the polar equation [tex]\( r = -3 + 5 \sin \theta \)[/tex] is [tex]\( 2 \)[/tex].

Among the given choices:
a. 8
b. 5
c. 2
d. 3

The correct answer is [tex]\(\boxed{2}\)[/tex].