Question

圆中,弦长6米,求半径及弧长,RT

Answer 1

弦长L=6米,拱高H=2米,求半径R及弧长C?

R=(L^2+4*H^2)/(8*H)

=(6^2+4*2^2)/(8*2)

=(36+16)/16

=52/16

=3.25米

圆心角A=2*ARC SIN(L/(2*R))

=2*ARC SIN(6/(2*3.25))

=2*ARC SIN(0.92308)

=67.38度

=67.38*PI/180

=1.176弧度

C=A*R

=1.176*3.25

=3.822米

半径为3.25米,弧长为3.822米.