已知tan a=-1/3,求4sin a-2cos a/5cos a+3sin a=

来源：学生作业帮助网编辑：六六作业网时间：2024/05/12 05:51:38

已知tana=-1/3,求4sina-2cosa/5cosa+3sina=已知tana=-1/3,求4sina-2cosa/5cosa+3sina=已知tana=-1/3,求4sina-2cosa/5

已知tan a=-1/3,求4sin a-2cos a/5cos a+3sin a=
已知tan a=-1/3,求4sin a-2cos a/5cos a+3sin a=

已知tan a=-1/3,求4sin a-2cos a/5cos a+3sin a=
(4sin a-2cos a)/(5cos a+3sin a)=(4tana-2)/(5+3tana)=(-4/3-2)/[5+3(-1/3)]
=(-10/3)/4=-10/12=-5/6