若0〈θ〈π/2,则 根号1-sinθ 等于
问题描述：
若0〈θ〈π/2,则 根号1-sinθ 等于
答
但是角度的范围是0到π/4根本不用分类吧
答
根号(1-sinθ)
=根号[1-2sin(θ/2)*cos(θ/2)]
=根号[sin^2(θ/2)+cos^2(θ/2)-2sin(θ/2)*cos(θ/2)]
=根号{[sin(θ/2)-cos(θ/2)]^2}
=|sin(θ/2)-cos(θ/2)|
由0〈θ〈π/2
当0