trick to remember all trigonometric identities

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3:21

13:31

کوتاه

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3:41

19:08

کوتاه

3:57

3:40

3:24

3:23

3:23

3:24

کوتاه

5:25

1:37

2:41

5:49

3:16

9:15

2:24

کوتاه

4:14

4:21

3:16

3:39

4:24

6:58

14:27

5:33

12:41

1:35

4:16

16:36

2:55

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