弧=1959.935883半径=981.25圆心角=114.4418387°圆心角所对扇形面积=(114.4418387/360)*π*981.25*981.25=961593.5427 三角形面积=438281.25弓形弧面积=523312.2927 半径=高/2+弦长*弦长/(8*高)圆心角=2*ArcSIN((弦...