设P(a,b).a²/9-b²/16=1①.F1P斜率t1=b/(a+5).F2斜率t2=b/(a-5).
tan60°=√3=(t2-t1)/(1+t1t2).代入化简得a²=(10b/√3)+25-b²②
②代入①,化简得25b²-(160b/√3)-256=0解得b≈5.543.S=5b≈27.71
设P(a,b).a²/9-b²/16=1①.F1P斜率t1=b/(a+5).F2斜率t2=b/(a-5).
tan60°=√3=(t2-t1)/(1+t1t2).代入化简得a²=(10b/√3)+25-b²②
②代入①,化简得25b²-(160b/√3)-256=0解得b≈5.543.S=5b≈27.71