Question

三道简单数学解三角形…求过程在△ABC中,B=30°,C=45°,C=1.求b边、三角形外接圆半径在△ABC中,A=60

Answer 1

(1)b/sinB=c/sinC=2R

解得b=√2/2，R=√2/2

(2)sinB=sin(45+60)=(√6+√2)/4

a/sinA=b/sinB=c/sinC

解得a=√3，b=(√6+√2)/2，B=75°

(3)a/sinA=b/sinB(A

B=60°，C=75°，c=√6+√2

B=120°，C=15°，c=√6-√2