Given the transformation:
Stretches the sine function vertically by a factor of 3.
Let's write the sine function that shows the transformation.
Let's first write out the parent sine function:

Now, apply the transformation rule for functions to write the function as it stretches the sine function vertically by a factor of 3.
We have:

Therefore, the sine function which show the given transformation is:
y = 3sinx
ANSWER:
