cos^α-sin^α/1+2sinαcosα=1-tanα/1+tanα

来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/23 12:03:13
cos^α-sin^α/1+2sinαcosα=1-tanα/1+tanαcos^α-sin^α/1+2sinαcosα=1-tanα/1+tanαcos^α-sin^α/1+2sinαcosα=1-

cos^α-sin^α/1+2sinαcosα=1-tanα/1+tanα
cos^α-sin^α/1+2sinαcosα=1-tanα/1+tanα

cos^α-sin^α/1+2sinαcosα=1-tanα/1+tanα
(cos^α-sin^α)/(1+2sinαcosα)
=(cosα-sinα)(cosα+sinα)/(sinα+cosα)^2
=(cosα-sinα)/(sinα+cosα)(分子分母同时除以cosα)
=(1-tanα)/(1+tanα)