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#1 2013-01-29 22:21:20

Power Member


Sine Cosine Tangents

I finally learned how to do sines, cosines, and tangents of triangles. (Seriously, if you found out my age, you might be surprised smile) 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. wink

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.

- n872yt3r
Math Is Fun Rocks! smile
By the power of the exponent, I square and cube you! cool

#2 2013-01-30 00:35:49

bob bundy


Re: Sine Cosine Tangents

hi n872yt3r

Or point people to the excellent MIF pages, such as


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

#3 2013-01-30 00:39:07

Super Member


Re: Sine Cosine Tangents

yeah.I know sine,


#4 2013-01-30 01:01:47

Real Member


Re: Sine Cosine Tangents

Hi n872yt3r

And how old are you, if I may ask?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#5 2013-01-30 01:27:24



Re: Sine Cosine Tangents

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.

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