C because if the line Q is 1,5 and 1,8, it would have to be a vertical line, as the X axis doesn’t change. As i know, a vertical line always has a slope of 0, and a horizontal line (which the x-axis is) always has an undefined slope.
Answer:
Acute
Step-by-step explanation:
Cos9x - cos5x = -2sin2x.sin7x
sin17x - sin3x = 2sin7x.cos10x
so f(x) =

=
0.018 will be 18/1000 = 9/500