Answer:
Positive direction (Up) 

Explanation:
The given function is 

The degree of this polynomial is even.
The leading coefficient is positive 3.
The polynomial will rise 
 on the left and rise
 on the left and rise 
 on the right.
on the right.
Therefore the right side of the graph of 
 points in the positive direction of the y-axis.
 points in the positive direction of the y-axis.