Question 682055
(a1)cos(b1) + (a2)cos(b1+b2) = p


(a2)cos(b1+b2) = p - (a1)cos(b1)


cos(b1+b2) = [ p - (a1)cos(b1) ]/(a2)


b1+b2 = arccos{ [ p - (a1)cos(b1) ]/(a2) }


b2 = arccos{ [ p - (a1)cos(b1) ]/(a2) } - b1