Expert: Richard J. Raridon - 10/22/2006

Question
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What is a hypotenuse and what is a adjacent side? Also on the calculator you would push 40 and then the sin button for sin40degrees?
The text above is a follow-up to ...

-----Question-----
I do not understand the whole sin and cos thing. I have a question I am stuck on and I have to multiply sin40degrees by another number. How do I do that? Do i have to convert 40 degrees into something? Do i need a calculator to do this?
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Yes, you need a calculator or a table of sine values which we had to use before the days of calculators.  If you consider one of the angles in a right triangle, the sine of the angle is the ratio of the opposite side to the hypotenuse.  The cosine is the ratio of the adjacent side to the hypotenuse.  If you have something simple like
a 3-4-5 right triangle, then the sine is 0.6 and the cosine is 0.8

Answer
How can you take physics without having had trigonometry?  Can you draw a right triangle?  If the two smaller sides are a and b, then the largest side, c, is the hypotenuse and there's a relationship, a^2 +b^2 = c^2.  Pick one of the non-90 degree angles.  You can obviously see which side is opposite.  The other small side is adjacent, which means "next to".