Question #02b52

1 Answer
Mar 17, 2017

see explanation.

Explanation:

Case 1.
enter image source here

sinangleCAD=SinA=(CD)/(AC)sinCAD=sinA=CDAC
=> CD=AC*sinA=b*sinACD=ACsinA=bsinA --- (1)

sinangleCBD=SinB=(CD)/(BC)sinCBD=sinB=CDBC
=> CD=BC*SinB=a*sinBCD=BCsinB=asinB ---(2)

(1) = (2), => b*SinA=a*SinBbsinA=asinB

=> SinA/a=sinB/bsinAa=sinBb

Case 2.
enter image source here

sinangleCAD=SinA=(CD)/(AC)sinCAD=sinA=CDAC
=> CD=AC*sinA=b*sinACD=ACsinA=bsinA --- (1)

angleCBA=angleBCBA=B
angleCBD=180-angleBCBD=180B
sinangleCBD=Sin(180-B)=sinB=(CD)/(BC)sinCBD=sin(180B)=sinB=CDBC,
=> CD=BC*SinB=a*sinBCD=BCsinB=asinB ------(2)

(1) = (2), => b*SinA=a*SinBbsinA=asinB

=> SinA/a=sinB/bsinAa=sinBb