sin 15 and sin 18 and cos 36: Pure geometric way

sin 15 and sin 18 and cos 36: Pure geometric way

More interesting math questions:
https://www.youtube.com/playlist?list=PLg9w7tItBlZsC-FFxBJxFg3dkCFGUqXIR

Instagram account: https://www.instagram.com/mathphyen/

Subscribe to my channel

more video lists:
################
機率

Probability and discrete mathematics:

######################################################################

Probability interview questions:

https://www.youtube.com/watch?v=qphhG_1rWf8&list=PLg9w7tItBlZtI1eM6znSYfyDEaqQtUx5b

Probability theory:

https://www.youtube.com/watch?v=8s-nyRLBsDo&list=PLg9w7tItBlZsvciKHBx8lXXnCtQ7Ou4cV

Complex analysis:

https://www.youtube.com/playlist?list=PLg9w7tItBlZsYfYG6dUISItqsSRSXaX4B

Combinatorics:

https://www.youtube.com/playlist?list=PLg9w7tItBlZvQt0YNfCqcULzrPme2ai7K

additive combinatorics:

https://www.youtube.com/playlist?list=PLg9w7tItBlZseUrmXgf_2yc2NI_obVUhB

微積分 高等微積分 代數

Calculus and advanced mathematics (abstract algebra):

######################################################################

Real analysis

https://www.youtube.com/playlist?list=PLg9w7tItBlZumEJ4DacAKgstCvDHKtY63