Question

加急!已知弦长5米,半径r1为4.25米,半径r2为4.6米,如图所示,求圆心角,扇形面积

Answer 1

扇形的圆心角:X=2*arcsin(5/2/4.25)=2*0.62887=1.2577=72.06°;

扇形面积=X/(2л)*(4.6^2-4.25^)=1.2577*3.0975/(2л)=0.62;