0.4663076582
写成连分数:倒数,整数+小数,小数倒数=整数+小数,依次类推,整数部分写出是下面形式
=1/(2+1/(6+1/(1+1/(11+1/(1+1/(1+1/(18+1/(1+1/(1+1/(3+1/(16+1/(3+1/(15+1/(13+1/1.866984786)
渐近分数:
1/2,
1/(2+1/6)=6/13
1/(2+1/(6+1/1)=1/(2+1/7)=7/15√=0.4666....
1/(2+1/(6+1/(1+1/11)=1/(2+1/(6+11/12)=1/(2+12/83)=83/178=0.46629
1/(2+1/(6+1/(1+1/(11+1/1)=1/(2+1/(6+1/(1+1/12)=1/(2+1/(6+12/13)
=1/(2+13/90)=90/193=0.46632
可取7/15,或83/178,90/193
tan25=sin25/cos25