f-BC : BD s= i.g6g347 g

tang (go° — { DBC) = 57° o' o" 0.1874826

lang ~ (BCD — BDC) === 1.22.23 8.37g632Ô

BCD = 58.22.23 BDC = 55.37.37.

1DKC = 35.57.2i .5 g0'— |DRC = 56. 2.38.5 = CDK BDC = 55.57.57

BDK == o.25. 2 ^BDK = 0.12.51 go° — £ BDR = 89.47-29-

LIVRE III DE LA SYNTAXE MATHÉMATIQUE. i35 Sin DBC : sin BCD :: DC : BD , et DC = asin | DKC.