task/29726620 см ПРИЛОЖЕНИЕ
9.084 c² =a²+b² -2abcosC =8²+10² -2*8*10*43/160 =64+100 -43 = 121 ⇒c =11.
9.085. b/2=c*sin(β/2)⇔b=2c√[(1-cosβ)/2) ] ⇔b=2*19√[(1 -7/8)/2] =2*19*1/4 =9,5.
9.085 10 /sinα = 5/sinβ ⇔ sinα= 2sinβ ⇔sin(90+β)= 2sinβ ⇔ cosβ =2sinβ ⇒
tgβ = 1/2 .