缬沙坦氢氯噻嗪 安明:tan(x+y)=0.4,tan(y-45°)=0.25,则tan(x+45°)=?要过程

来源:百度文库 编辑:高校问答 时间:2024/03/29 20:16:50

因为(x+y)-(y-45°)=x+45°
所以tan[(x+y)-(y-45°)]=tan(x+45°)
左边展开:
tan(x+45°)
=[tan(x+y)-tan(y-45°)]/[1+tan(x+y)*tan(y-45°)]
=(0.4-0.25)/(1+0.4*0.25)
=3/22

tan(x+y)=tanx+tany/(1-tanxtany)=0.4
由此可得tany=5/3 tanx=(不算了) 再由公式得结果

tan(x+45°)=tan[(x+y)-(y-45°)]
=[tan(x+y)-tan(y-45°)]/[1+tan(x+y)*tan(y-45°)]
=(0.4-0.25)/(1+0.4*0.25)
=0.15/1.1
=3/22