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anonymous
 one year ago
please help... calc will be the death of me lol
anonymous
 one year ago
please help... calc will be the death of me lol

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@ikram002p heyy any idea here lol

idku
 one year ago
Best ResponseYou've already chosen the best response.0this is calculus, are you sure?

idku
 one year ago
Best ResponseYou've already chosen the best response.0sin(30)=1/2 mutliply both sides times 1 and use the rule sin(k)=sin(k)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0wait so how did you decide to do sin 30

idku
 one year ago
Best ResponseYou've already chosen the best response.0As for your second problem dw:1440615688714:dw

idku
 one year ago
Best ResponseYou've already chosen the best response.0how you decide to do for sin(30)? what do you want to know?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0lets just work on the first one im wayy too lost lol so you drew a reference triangle?

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1when you have negative values of a trig ratio you might find it easier to remember their signs in the 4 quadrants 0  360 degrees

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1dw:1440615941625:dw

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1so they are ALL positive in first quadrant (0 to 90 degrees) Only the sine is positive in 2nd quadrant, only the tangent in the third and only the cosine in the 4th quadrant  otherwise they are negative

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1so if you have sine x = 0.5 Sine 30 is 0.5 ( thats first quadant) its negative in 2nd and 3rd so 2 values for the angle would be 18030 = 150 and 180+ 30 = 210 these are the results if the question asks for values of the angle in range 0 to 360 degrees.

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1oh i messed up there sorry! sine is negative in 3rd and 4th quadrants so thats 210 and 330 dgrees!!

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0phew i got nervous for a sec i was like wuttt... but i get that so far

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1dw:1440616444926:dw

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1dw:1440616515975:dw

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1personally i find it easier to use pictures with these problems.

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1theres 2 triangles worth remembering the one that idku posted and also the 454590 triangle

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1dw:1440616730872:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0alrigh but for this [prob im dealing with the 30 60 90

welshfella
 one year ago
Best ResponseYou've already chosen the best response.12 cos x = sqrt3 cos x = sqrt3/2 so what is the value of angle x ( from the 30 60 90 triangle)?

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1remember cosine = adjacent / hypotenuse

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1maybe the presence of the S is confusing you ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so would i tak inverse cos (sqrt3/2) to find the angle

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1yes  or you can see it on the diagram dw:1440617639361:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0when i do it the way i said i get a domain error

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0wait can we stick with #1 for now im trying to understand it

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so i get how you found 210 and 330

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1440617866896:dw

phi
 one year ago
Best ResponseYou've already chosen the best response.0when you have time, you might want to review https://www.khanacademy.org/math/trigonometry/unitcircletrigfunc/Trigunitcircle/v/unitcircledefinitionoftrigfunctions1

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0ignore that drawing. i just watched a tutorial. so the question is asking me for the angle measure correct?

phi
 one year ago
Best ResponseYou've already chosen the best response.0personally I would solve this \[ \sin x =  \frac{1}{2} , \text{ for } 0 \le x \lt 2 \pi\] but graphing (sketching actually) sin x from 0 to 2pi dw:1440619769364:dw

phi
 one year ago
Best ResponseYou've already chosen the best response.0looking at the curve, it should be clear there are two angles where sin x = 1/2 we should have memorized some "standard angles" in particular sin 30º = 1/2 thus the solutions will be 30º *in the correct quadrants* in particular 180+30 =210 (but put in radians) and 36030 = 330º, but put in radians.

phi
 one year ago
Best ResponseYou've already chosen the best response.0for 2 cos x = sqr(3) \[ \cos x = \frac{\sqrt{3}}{2} \] dw:1440620036903:dw again, two solutions we should know cos 30º = sqr(3)/2 thus 30 and 36030 = 330º

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay i understand much bette. the way i learned from the tutorial is to isolate the x and then look for it on the unit circle to find possible soulutions and then determine the correct quadrants

freckles
 one year ago
Best ResponseYou've already chosen the best response.0dw:1440621102930:dw
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