Answer:
19
Step-by-step explanation:
Given 2 sides of a triangle then the third side x is
difference of 2 sides < x < sum of 2 sides , that is
18 - 2 < x < 18 + 2
16 < x < 20
Then the largest possible length of the third side is 19
baka
Equate whats inside (arguments) with base period of sine function and solve for x to get period,
So the period of the graph of the given function is precisely 2.
Hope this helps :)