X_(1,2)= (-5+7)/6

To simplify the expression \( X_{(1,2)} = \frac{-5 + 7}{6} \): 1. First, calculate the numerator: \[ -5 + 7 = 2 \] 2. Now, substitute this back into the fraction: \[ X_{(1,2)} = \frac{2}{6} \] 3. Finally, simplify the fraction: \[ \frac{2}{6} = \frac{1}{3} \] So, \( X_{(1,2)} = \frac{1}{3} \).