Why are the graphs of our trigonometric functions (sine and cosine) considered to be periodic?

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H H I H III HC- --- -CLcLH IUI H I Number of Carbon Atoms Number of Carbon Atoms Prefix Prefix 1 11 meth- eth- undec dodec 2 12 8 tridee 13 prop but- 15 6 16 pent hex hept. OCE 7 tetradec pentades hexadec heptadec octadec nonades cicos 17 8 18 9 19 non- dec 10 20 How many Carbons are in the longest possible chain? Choose What prefix do we use for that many Carbons in a main chain? Choose How many substituents (add-ons) are there? Choose What Carbon number is the substituent (add-ons) on? Choose