Question

若√(1-sin x)/(1+sin x)=(sin x-1)/cos x,则x的取值范围是

Answer 1

√((1-sin x)/(1+sin x))=√((1-sinx)^2/(cosx)^2)=(1-sinx)/|cosx|

由已知可得(1-sinx)/|cosx| = (sinx -1)/cosx,所以cosx