三角函数问题 求解 急!!
公式:R=b/2*tg{[arctg(B-b)/2h]/2}1.B=19.6 b=15 h=202.B=31.2 b=21 h=26求R=????
参考答案:1.R=15/2*tg{[arctg(19.6-15)/2*20]/2}
=7.5*tg{[arctg(4.6)/40]/2}
=7.5*tg{[1.36/40]/2}=0.127
2.0.149
公式:R=b/2*tg{[arctg(B-b)/2h]/2}1.B=19.6 b=15 h=202.B=31.2 b=21 h=26求R=????
参考答案:1.R=15/2*tg{[arctg(19.6-15)/2*20]/2}
=7.5*tg{[arctg(4.6)/40]/2}
=7.5*tg{[1.36/40]/2}=0.127
2.0.149