在三角形ABC中,已知b+a除以a=sinB除以sinB-sinA,且2sinAsinB=2sin^2C,求a+c除以b取值范围
<p>问题：在三角形ABC中,已知b+a除以a=sinB除以sinB-sinA,且2sinAsinB=2sin^2C,求a+c除以b取值范围<p>答案：↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">程岷沙的回答：<div class="content-b">网友采纳 因为(a+b)/a=sinB/(sinB-sinA),所以(a+b)/a=b/(b-a),∴ab=b^2-a^2,-------(1),∵cos(A-B)+cosC=1-cos2C,∴cos(A-B)-cos(A+B)=1-cos2C∴2sinAsinB=2(sinc)^2,∴ab=c^2--------(2),由（1）（2）两式得：a^2+c^2=b^2,∴...
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