All credits due to my math teacher from high school in Vietnam in 2003. His name is Hai.
Your feedbacks are much appreciated for future tutorials. If ya like it, feel free to pass it along, post it on facebook etc... please help other people who are struggling.
Tangent is Sin/Cos so you just take the number of fingers on the left divided by the right and take square root of the result.
duydaniel 1 year ago