Question

一條弧所對(duì)的圓心角為72°，則這條弧所對(duì)圓周角為

 

．

Answer 1

分析：因?yàn)橥�弧所�?duì)的圓周角等于它對(duì)圓心角的一半，所以這條弧所對(duì)圓周角為36°．

解答：解：∵一條弧所對(duì)的圓心角為72°，
∴這條弧所對(duì)圓周角為：72°×

1

2

=36°．
故答案為：36°．

點(diǎn)評(píng)：此題考查了同弧所對(duì)的圓周角等于它對(duì)圓心角的一半的性質(zhì)．題目很簡(jiǎn)單，解題時(shí)要細(xì)心．