问题 选择题 已知am=4,an=3,则a3m-2n=( )A.8B.55C.649D.2 答案 ∵am=4,an=3,∴a3m-2n=a3m÷a2n=(am)3÷(an)2=43÷32=64÷9=649.故选:C.