20/11/18 07:27:19.43 l55DpzKJ.net
>>538-539 (上)
ついでながら、AB^2 = x とおくと
正弦定理より
BC^2 = pp x,
CA^2 = qq x,
ここに
p = sin(50)/sin(60) = sin(50)･2/√3,
q = sin(70)/sin(60) = sin(70)･2/√3,
x を求める式は (イナ氏)
sqrt((49-p*p*x)*(p*p*x-1)) + sqrt((36-q*q*x)*(q*q*x-4)) + sqrt((25-x)*(x-1)) - sqrt(3)*p*q*x = 0, where p= 0.884551930891917861607228426181188396289151, q=1.085063575132498257126257622997857631052135
計算結果
x = 24.372365795851178986638086448179657137312
AB = √x = 4.9368376311006197590325370488442433561053
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