已知A=1弧度的圆心角所对的弦长是L=2，求圆心角所对的弧长C和圆心角所在的扇形的面积S?弧半径为R。A=1弧度=180/PI=57.296度R=(L/2)/SIN(A/2) =(2/2)/SIN(57.296/2) =2.0858C=R*A=2.0858*1=2.0858S=PI*R^2*A/360 =PI*2.0858^2*57.296/360 =2.175
