`E^(2)=E_(1)^(2)+E_(2)^(2)+2E_(1)E_(2) cos 120^(@)`
`E_(1)=(100)/(5^(2)) " और "E_(2)=(50)/(5^(2))`
`therefore " "tan theta=(E_(1) sin 120^(@))/(E_(2)+E_(1)cos 120^(@))`
`cos 120^(@)=(1)/(2), sin 120^(@)=(sqrt3)/(2)`
5.291 डाइन प्रति स्थैत कूलॉम BC के लंबवत