作业帮 > 数学 > 作业

求证:Sin^2 x / (sinx-cosx) - (sin x + cos x)/(ta

来源:学生作业帮 编辑:大师作文网作业帮 分类:数学作业 时间:2024/09/21 22:39:14
求证:Sin^2 x / (sinx-cosx) - (sin x + cos x)/(ta
求证:Sin^2 x / (sinx-cosx) - (sin x + cos x)/(tan^2-1) = sin x + cos x
求证:Sin^2 x / (sinx-cosx) - (sin x + cos x)/(ta
原式=sin^2 x/(sinx-cosx)-(sinx+cosx)/(sin^2 x/cos^2 x-1)=sin^2 x/(sinx-cosx)-(sinx+cosx)*cos^2 x/(sin^2 x-cos^2 x)=(sin^2 x-cos^2 x)/(sinx-cosx)=sinx+cosx