The coolest fact in trigonometry that you learn way too late....by Femme_physics Tags: coolest, fact, late, learn, trigonometry 

#1
Sep2410, 12:39 PM

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So I just spent the last 12 hours learning trig (occasional food breaks).
I just want to share with you something really, really, really, really, awesome. Check this out, you're gonna be blown away The law of cosines, applied to a right triangle is c^2 = a^2+b^2  2abCosA Whereas A is equal to zero!!! So the law of cosines for a right triangle is, in fact, the Pythagorean theorm!!! Math is sooooooooo awesome. Why did it only take me the last quarter of the textbook to learn this fact??? 



#2
Sep2410, 12:42 PM

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P: 1,344

Perhaps I'm missing something here, but if A = 0, cos A = 1, and your statement comes in as
[tex] c^2 = a^2 + b^2  2ab [/tex] which is not the Pythagorean Theorem. 



#3
Sep2410, 12:46 PM

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I mean, A is 90 degrees and therefor 0 is equal to 0!!!
Sorry 



#4
Sep2410, 01:32 PM

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The coolest fact in trigonometry that you learn way too late....yep it's awesome 



#5
Sep2410, 01:45 PM

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A  B  CThen the length of the whole (b) is the sum of the lengths of the two parts (a and c). 



#6
Sep2410, 02:59 PM

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You'll find lots of cool things in your math classes if you take the time to look around. 



#7
Sep2410, 07:10 PM

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#8
Sep2410, 09:18 PM

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