π=圆周长/直径≈内接正多边形/直径。当正多边形的边长越多时,其周长就越接近于圆的![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/4a36acaf2edda3ccda6e4db313e93901203f929f?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
π(圆周率)前两百位3.14159265358979323846264338327950288419716939937510582097494459230781640628620899862803482534211706798214808651328230664709384460955058223172535940812848111745028410270193852110555964462294895493038196