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*HELP* Finding x in [_,_] of Possible Inflection Points 
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#19
Jan1509, 09:15 PM

P: 55

if you just do sin^{1} (0.6180) = 0.6662 > only one value, i need 2 values 


#20
Jan1509, 09:18 PM

P: 626

OK let's pick a simpler example. If you had to find sin(x) = 1/2 how would you figure out x?



#21
Jan1509, 09:19 PM

P: 55




#22
Jan1509, 09:20 PM

P: 626

lol sure, but if you didn't have a calculator, how would you figure that one out.



#23
Jan1509, 09:24 PM

P: 55




#24
Jan1509, 09:26 PM

P: 626

You should go back and review trigonometry. It's on the unit circle.



#25
Jan1509, 09:34 PM

P: 55

come on help me out here (your name), lol ok fine soooo...
sinθ = y/r > y=1 and r=2 using THE theorem x=sqrt3 ??? 


#26
Jan1509, 09:37 PM

P: 626

You can look the answer up on wikipedia, it's a common angle and it was already addressed in this thread I believe.



#27
Jan1509, 09:49 PM

P: 55

okay Im not sure what your getting at, I know that sin(π/6) = 1/2 and sin(5π/6) = 1/2



#28
Jan1509, 09:56 PM

P: 626

I'm trying to get you to remember how those values were determined. Sin(pi/6) = 1/2 is easy. So we know 30 degrees is what we need. Since we have sine, it's positive in 1st and 2nd quadrants. So in the first quadrant we have 30 degrees, in the 2nd we know our "line" must make a 30 degree angle with the horizontal which would be pi, so we did pi  pi/6 = 5pi/6



#29
Jan1509, 10:02 PM

P: 55

oh ok so my number is not 1/2 but 0.6180 so that is 38.17degrees
so the line must make a 38.2degree angle with the horizontal since pi is (180degrees) 18038.2 = 141.2degrees ~2.46rad is this the answer? 


#30
Jan1509, 10:06 PM

P: 626

Well try plugging that into your calculator :)



#31
Jan1509, 10:14 PM

P: 55




#32
Jan1509, 10:14 PM

P: 626

There you go champ :)



#33
Jan1509, 10:17 PM

P: 55

thanks (still didnt tell me your name) :) now i just have to finish the rest of the assignment lol



#34
Jan1509, 10:20 PM

P: 626

The beauty of the anonymity of the Internetz ;)



#35
Jan1509, 10:22 PM

P: 55




#36
Jan1509, 10:23 PM

P: 626

Genius  far, far, far from it but you are welcome.



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