To find the y-intercept of the exponential function \( y = 2 \left( \frac{3}{1} \right)^x \), we need to evaluate the function at \( x = 0 \).
So, substituting \( x = 0 \) into the function:
\[ y = 2 \left( \frac{3}{1} \right)^0 \]
Since any number raised to the power of 0 is 1:
\[ y = 2 \cdot 1 = 2 \]
Thus, the y-intercept is \( 2 \).