已知sinθ=3/5,θ为锐角,则sinθ/2=
问题描述:
已知sinθ=3/5,θ为锐角,则sinθ/2=
答
θ为锐角
cosθ=4/5
=1-2(sinθ/2)^2
(sinθ/2)^2=1/10
θ为锐角
sinθ/2=根号10/10