Answer:
they are identical. proved below.
Step-by-step explanation:
- formula: [tex]sin(t)+sin(s) = 2sin(\frac{t+s}{2} )cos(\frac{t-s}{2} )[/tex]
using the formula to proof:
[tex]sin9a+sin5a[/tex]
[tex]2sin(\frac{9+5}{2})* cos(\frac{9-5}{2})[/tex]
[tex]2sin7a * cos2a[/tex]
True. proved that they are identical.
