________________
Figure 1. Regular Polygon of n-sides
The degree of accuracy of An given by (1.21) may be accessed by calculating the percentage error En as:
1 An En = [ Aon - 1] x 100 = [
n2 - 4 3ntan (/n - 1] x 100.
Table 1A show the percentage error if one uses the formula (1.21) for different values of n.
Table 1A
E3 = 3.77 E4 = 0 E5 = 1.72 E6 = 2.64
E10 = 3.97 E20 = 4.53 E30 = 4.64 E00 = 4.72
The applicability of An given by (1.23) may also be estimated by computing the percentage of error En below (see Table 1B)
En = [
n-1
3
tan (Tu/n - 1] x 100.
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