∵△ABC中,A+B+C=π,∴C=π-(A+B),又tanA=t+1,tanB=t-1,∴tanC=-tan(A+B)=- tanA+tanB 1?tanAtanB = tanA+tanB tanAtanB?1 = 2t t2?2 ,∵△ABC为锐角三角形,∴tanA>0,tanB>0,tanC>0,即 t+1>0 t?1>0 2t t2?2 >0 解得t> 2 .∴t的取值范围是t> 2 .故选D.