过双曲线9分之x²-16分之y²=1左交点F1作倾斜角4分之π的直线为双曲线交于A、B两点

a = 3,b = 4c = √(3² +4²) = 5F1(-5,0)直线斜率 = tan(π/4) = 1直线:y - 0 = x +5,y = x + 5x²/9 - (x+5)²/16 = 17x² - 90x - 369 = 0x₁ + x₂ = 90/7x₁x₂ = -36...