Answer:

Step-by-step explanation:
I'm going to write 105 as a sum of numbers on the unit circle.
If I do that, I must use the sum identity for sine.


Plug in the values for sin(60),cos(45), sin(45),cos(60)



The numerator could be written a⁴/⁵
The denominator could be written a²/³
Now solve ( a⁴/⁵) / (a²/³) ==> a⁽⁴/⁵ ⁻²/³) = a⁽²/¹⁵)
This is the simplest way