来源:学生作业帮 编辑:神马作文网作业帮 分类:数学作业 时间:2024/11/13 09:57:10
请问这个正弦定理的变形公式是怎样得到的?
a/sinA=b/sinB=c/sinC=k
=>a=ksinA,b=ksinB,c=ksinC
=>a+b+c=ksinA+ksinB+ksinC=k(sinA+sinB+sinC)
=>(a+b+c)/(sinA+sinB+sinC)
=k(sinA+sinB+sinC)/(sinA+sinB+sinC)
=k
=a/sinA
=b/sinB
=c/sinC