【在△ABC中,角A,BC的对边长分别为abc,B=π/3,CosA=4/5,b=根号3,求sinC的值,求△ABC的面积在△ABC中,角A,BC的对边长分别为abc,B=π/3,CosA=4/5,b=根号3,求sinC的值,求△ABC的面积】
<p>问题：【在△ABC中,角A,BC的对边长分别为abc,B=π/3,CosA=4/5,b=根号3,求sinC的值,求△ABC的面积在△ABC中,角A,BC的对边长分别为abc,B=π/3,CosA=4/5,b=根号3,求sinC的值,求△ABC的面积】<p>答案：↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">宋仁学的回答：<div class="content-b">网友采纳 cosA=4/5sinA=√=3/5sinC=sin(π-A-B)=sin(A+B)=sinAcosB+cosAsinB=(3/5)cos(π/3)+(4/5)sin(π/3)=(3/5)(1/2)+(4/5)(√3/2)=(3+4√3)/10由正弦定理,a/sinA=b/sinBa=bsinA/sinB=(3/5)√3/(√3/2)=6/...
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