You have the right idea. You multiply the exponents. However, you did not multiply the denominators 6 and 6 to get 36
So you should have 12/36 reducing to 1/3 as your final exponent
Therefore, the answer is 6^(1/3) which is the same as the cube root of 6
Side note: you don't need to turn 2/3 and 1/2 into fractions with a denominator of 6. You can multiply straight across and simplify
(2/3)*(1/2) = (2*1)/(3*2) = 2/6 = 1/3