MathematicsMedium64×since 2002Q2911If the coefficients of x^−2 and x^−4 in the expansion of (x13+12x13)18,(x>0),{\left( {{x^{{1 \over 3}}} + {1 \over {2{x^{{1 \over 3}}}}}} \right)^{18}},\left( {x > 0} \right),(x31+2x311)18,(x>0), are m and n respectively, then mn{m \over n}nm is equal to :A182B45{4 \over 5}54C54{5 \over 4}45D27Check answerSkip