Question

2 questions...

Answer 1

Determine if the graph is symmetric about the x-axis, the y-axis, or the origin. (5 points)

r = 5 + 4 cos θ

x-axis only
y-axis only
No symmetry
Origin only

Answer 2

Find an explicit rule for the nth term of the sequence. (5 points)

7, -7, 7, -7, ...

an = 7 • (-1)n - 1
an = 7 • (-1)n
an = 7 • 1n - 1
an = 7 • 1n + 1

Answer 3

Given that the graph of cosine function is like the picture below:
.
The 4 that multiplies the cos, means that every value of y is going to increase by a factor of 4. At the end, the shape remains and it is just that the graph is more stretched vertically.
The 5 that adds the function, means that every coordinate has to increase by 5 at the y-coordinate. In this scenario, the graph will basically move upwards in the y-axis, but still maintaining the same shape.

Ultimately, the graph still has a symmetry in the y-axis.
Therefore, answer is A.