SinA= opposite/hypotenuse
sinA= 12/13
Answer:

Step-by-step explanation:
Given


Required
Write the equivalent cosine function
The general formula is:

Where


Substitute
for amplitude in 


Substitute 3 for period in 

<em>Multiply both sides by b</em>

<em>Divide through by 3</em>

Hence;
becomes

Anddddddddddddd? what else?
Step-by-step explanation:
the solution is in the picture
343in3 is the answer to this math question