how to prove that pi>3?

2008-05-17 7:54 am

回答 (10)

2008-05-17 8:08 am
✔ 最佳答案
Consider a regular hexagon inscribed in a circle. The regular hexagon has a perimeter of 6 times the the radius (distance from the center to a vertex.

The straight sides of the hexagon are necessarily shorter than the curved arcs of the circle, so the circumference of the circle is greater than the perimeter of the hexagon.
C > P
C/r > P/r; but C = 2pi(r) and P/r = 6 as noted above.
2pi(r)/r > 6
pi > 3
2008-05-17 3:30 pm
Draw a circle that has a radius of 5 cm. so the perimeter of circle would be 10pi. Then take a string of length 30 cm and try to cover the perimeter of the circle. you will find out that the string of 30 cm of lenght is not long enough to cover the entire circle. So this proves that pi is greater that 3.
2008-05-24 2:05 pm
Go with Bart hes 100% correct.......
2008-05-18 5:23 pm
pi=22/7
on solving 22/7 we get 3.142857 which is clearly greater than 3!!
2008-05-17 10:00 pm
pi is 22/7 which is 3.14 >3
2008-05-17 5:59 pm
pi = 3.14......

pi > 3
3.14...... > 3
3.14...... - 3 > 0
0.14...... > 0
2008-05-17 3:10 pm
If pi were equal to 3 then our wheels would be hexagonal and we'd have a real bumpy ride!
2008-05-17 3:06 pm
by not listening to marissa
2008-05-17 3:06 pm
pi-3>0
2008-05-17 3:04 pm
click the pi symbol on your calculator. click equal.


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