tan^2α-sin^2α=tam^2α*sin^2α

来源：学生作业学帮网编辑：学帮网时间：2024/05/29 21:15:41

tan^2x-sin^2x=sin^2x/cos^2x-sin^2x=
(1/cos^2x-1)sin^2x=[(1-cos^2x)/cos^2x]sin^2x=
[sin^2x/cos^2x]sin^2x=tan^2xsin^2x