^2=ac
a^2=ac-bc+c^2=b^2+c^2-bc
余弦定理a^2=b^2+c^2-2bccosA
化简,
cosA=0.5
角A为60°
因b^2=ac
b/c=a/b
bsinB/c=asinB/b
正弦定理sinB/b=sinA/a
bsinB/c=asinB/b=asinA/a=sinA=二分之根号三
^2=ac
a^2=ac-bc+c^2=b^2+c^2-bc
余弦定理a^2=b^2+c^2-2bccosA
化简,
cosA=0.5
角A为60°
因b^2=ac
b/c=a/b
bsinB/c=asinB/b
正弦定理sinB/b=sinA/a
bsinB/c=asinB/b=asinA/a=sinA=二分之根号三