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The sum of all rational terms in the expansion of (1+21/3+31/2 )6 is equal to .
612
Term: 6!r1! r2! r3! (21/3 )r2 (31/2 )r3; rational r2 \0,3,6\, r3 \0,2,4,6\ with r1 0
(r1,r2,r3)=(6,0,0):1; (4,0,2):45; (2,0,4):135; (0,0,6):27
(3,3,0):40; (1,3,2):360; (0,6,0):4
Sum =612
Answer: 612
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