1. 2sina-3cosa/3sina-cosa分子分母同除以cosa原式=(2tana-3)/(3tana-1)=(4-3)/(6-1)=1/52.2sin²a-3cos²a/3sin²a-cos²a分子分母同除以cos²a原式=(2tna²a-3)/(3tan²a-1)=(8-3)/...