I finally learned how to do sines, cosines, and tangents of triangles. (Seriously, if you found out my age, you might be surprised ) I'm showing this for the younger ones out there.
A sine is the opposite side of the triangle divided by the hypotenuse. S=O/H. If you put this on a function grapher, like the one on Math Is Fun, or the CAS on GeoGebra, it makes a wave pattern.
A cosine is the adjacent side divided by the hypotenuse. C=A/H. If you put this on a function grapher, it also makes a wave pattern.
A tangent is the opposite side divided by the adjacent. T=O/A. On a circle, tangents are lines that touch the circle once, then go off... if you have two, it's like dumplings and chopsticks.
You can remember S=O/H, C=A/H, and T=O/A by thinking SOHCAHTOA. (so-cuh-to-uh)
Since I still can't upload pictures or links, I would appreciate posting a right angle with the corners labeled A, B, and C, the adjacent, hypotenuse, and opposite labeled, adjacent is A and C, opposite B and C, and hypotenuse A and B.
Math Is Fun Rocks!
By the power of the exponent, I square and cube you!
yeah.I know sine,
And how old are you, if I may ask?
Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
I would guess he is 9. And congratulations on learning about trigonometry.
In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.