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aussy123
 2 years ago
Given: costheta= 4/5, sin x =12/13 ,theta is in the third quadrant, and x is in the fourth quadrant; evaluate cos 2x.
119/169
119/169
11/13
aussy123
 2 years ago
Given: costheta= 4/5, sin x =12/13 ,theta is in the third quadrant, and x is in the fourth quadrant; evaluate cos 2x. 119/169 119/169 11/13

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satellite73
 2 years ago
Best ResponseYou've already chosen the best response.1you don't need the sine part

satellite73
 2 years ago
Best ResponseYou've already chosen the best response.1\[\cos(2x)=2\cos^2(x)1\]

tomhoffhim
 2 years ago
Best ResponseYou've already chosen the best response.0dw:1364529999084:dw

satellite73
 2 years ago
Best ResponseYou've already chosen the best response.1oh i see there is a \(\theta\) and an \(x\)

aussy123
 2 years ago
Best ResponseYou've already chosen the best response.0costheta= 4/5 I need cosx

satellite73
 2 years ago
Best ResponseYou've already chosen the best response.1you are asked for \(\cos(2x)\) where \(\sin(x)=\frac{12}{13}\)

satellite73
 2 years ago
Best ResponseYou've already chosen the best response.1\[\cos(2x)=12\sin^2(x)\]

aussy123
 2 years ago
Best ResponseYou've already chosen the best response.0When I do it I get 169

satellite73
 2 years ago
Best ResponseYou've already chosen the best response.1there is no \(\theta \) in your question

tomhoffhim
 2 years ago
Best ResponseYou've already chosen the best response.0ok, I'll do it for you, give me a second, this is an easy question

aussy123
 2 years ago
Best ResponseYou've already chosen the best response.0yea I had to put theta for that

tomhoffhim
 2 years ago
Best ResponseYou've already chosen the best response.0satellite, you don't know what you're doing..

satellite73
 2 years ago
Best ResponseYou've already chosen the best response.1\[\cos(x)=12\sin^2(x)\] \[\cos(x)=1(\frac{12}{13})^2\]\

satellite73
 2 years ago
Best ResponseYou've already chosen the best response.1\[\cos(2x)=1(\frac{12}{13})^2\] \[\cos(2x)=1\frac{144}{169}\]

satellite73
 2 years ago
Best ResponseYou've already chosen the best response.1\[\cos(2x)=\frac{25}{169}\]

aussy123
 2 years ago
Best ResponseYou've already chosen the best response.0I know, thats what I get, but it isnt a choice

satellite73
 2 years ago
Best ResponseYou've already chosen the best response.1your question asks for \(\cos(2x)\) and doesn't mention any \(\theta\)

aussy123
 2 years ago
Best ResponseYou've already chosen the best response.0I know but that is what is already given

satellite73
 2 years ago
Best ResponseYou've already chosen the best response.1oh damn i made a mistake!! sorry

tomhoffhim
 2 years ago
Best ResponseYou've already chosen the best response.0I'm too lazy to do it but you need to draw the triangles and either use theta or x for the angle

aussy123
 2 years ago
Best ResponseYou've already chosen the best response.0lol its okay, Ive made plenty

satellite73
 2 years ago
Best ResponseYou've already chosen the best response.1\[\cos(2x)=12\sin^2(x)\] \[\cos(2x)=12\times (\frac{12}{13})^2\] \[cos(2x)=12\times \frac{144}{169}\]

satellite73
 2 years ago
Best ResponseYou've already chosen the best response.1\[\cos(2x)=1\frac{288}{169}\]\[\cos(2x)=\frac{119}{169}\]

aussy123
 2 years ago
Best ResponseYou've already chosen the best response.0Lol this is a lot of work, can you use this same formula for tan2Theta

aussy123
 2 years ago
Best ResponseYou've already chosen the best response.0nvm. I found the formula, Thank you!
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