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anonymous
 5 years ago
which value of theta satisfies the equation 2cos^2theta  cos theta=0
anonymous
 5 years ago
which value of theta satisfies the equation 2cos^2theta  cos theta=0

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[cos^2(\theta)cos(\theta)=0\] \[cos(\theta)(cos(\theta)1)=0\] \[cos(\theta)=0\] or \[cos(\theta)=1\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oooooooops forgot the two!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ignore my post, or just modify with the two.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0is there a formula to memorize forthis?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[cos(\theta)(2cos(\theta)1)=0\] \[cos(\theta)=0\] \[cos(\theta)=\frac{1}{2}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oh no the first part has nothing at all to do with trig

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0costheta(2costheta1)=0 cost=0 => t=pi/2,3pi/2,... 2npi+pi/2 and 2npi+3p/2 for n=0,1,2,... 2cost1=0 => cost=1/2 => t=pi/3,11pi/6,.... 2npi+pi/3 and 2npi+11pi/6 for n=0,1,2..

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0like solving \[2x^2x=0\] \[x(2x1)=0\] \[x=0\] \[x=\frac{1}{2}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0the trig part comes now.

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0oops that 11pi/6 is wrong its 5pi/3

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0the first job is to solve for \[cos(\theta)\] the next step is to solve for \[\theta\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0the first steps have nothing at all to do with trig. no formulas, no nothing.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0think of \[cos(\theta)\] as x and solve for x. you have \[2x^2x=0\] and this is easy to solve

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0we get \[x=0\] or \[x=\frac{1}{2}\] so now \[cos(\theta)=0\] or \[cos(\theta)=\frac{1}{2}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0the trig part comes now, seeing if we can find numbers for theta that will make this work.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0can you do the next step, that is, can you find theta?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok so first off we want to find where \[cos(\theta)=0\]

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0just look between 0 and 2pi first to see where cosine is 0

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0best cheat sheet. look on it to see where cosine is 0. it is not at 0, because \[cos(0)=1\]

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0then after just add 2npi for n=0,1,2,3,... blah blah

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0cos is the x correct?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yes we already know x=0, so therefore \[cos(\theta)=0\] now we are looking for \[\theta\] that is we are looking for an angle (number) whose cosine is 0

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0what happens at pi/2?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0the very bottom of the cheat sheet i sent has all the angles associated with the unit circle, and all the coordinates. look on the unit circle to see where the first coordinate is 0

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0if you are working in degrees it is 90

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0radians \[\frac{\pi}{2}\]

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0is there another between 0 and 2pi, that cosine will be zero?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0but on my wksht theres noone of those answers.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0whatever you prefer. so that takes care of \[cos(\theta)=0\] for the moment. now we need \[cos(\theta)=\frac{1}{2}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yes 90 works, and 270 also works

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0or 3pi/2 now we can get cosine is 0 when we start at these angles and go around the circle again (2pi) so the answer for cos(t)=0 is t=2npi+pi/2 and t=2npi+3pi/2

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0you are working in degrees so you have the answers.

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0that whole paragraph is still talking about the first one k?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0theo nly answers available are pi over 6 0 pi/4 or pi/m3

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0then they are missing \[\frac{\pi}{2}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\frac{\pi}{3}\] works, from the cheat sheet

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0if those are your possible answers you are working in radians not degrees.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[2 \cos^2 \theta \cos \theta = 0\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i know but i like using degrees better.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so was pi/3 the answer? vecause cos was 1/2?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i semi get it,thank you

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i guess it just asked 'which one of these is a solution"

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0did you look at the cheat sheet? because it is a good one

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yeah which value satisfies the the equation

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yes, it had a lot of good material thank you

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0could you helo me with my other math questions?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.02 cos_th^2  cos_th = 0 cos_th (2 cos_th  1) = 0 > cos_th =0 or 1/2 > th = theta = +pi/2 or  pi/2 or pi/3 or +pi/3 *
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