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shaqadry
 3 years ago
solve 3 sin^2 x  2 = cos x
shaqadry
 3 years ago
solve 3 sin^2 x  2 = cos x

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tyteen4a03
 3 years ago
Best ResponseYou've already chosen the best response.0Remember that \(sin^2(x) + cos^2(x) = 1\).

ashwinjohn3
 3 years ago
Best ResponseYou've already chosen the best response.1Is 3 sin^2(x2)=cos x

tyteen4a03
 3 years ago
Best ResponseYou've already chosen the best response.0@ashwinjohn3 I believe it's 3sin^2(x)  2.

shaqadry
 3 years ago
Best ResponseYou've already chosen the best response.0yea its 3 sin^2 (x)  2 = cos (x)

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.0change sin^2 x to cos^2 x using \(\sin^2(x) + \cos^2(x) = 1\) then if you put cos^2 x = y, you'll get a quadratic in y.

ashwinjohn3
 3 years ago
Best ResponseYou've already chosen the best response.1ok... then,here \[\sin ^{2} x=1\cos ^{2} x\] \[3 (1\cos ^{2}x )2=33 \cos ^{2}x 2=13\cos ^{2}x\]

shaqadry
 3 years ago
Best ResponseYou've already chosen the best response.0thats what i get but then i cant figure out how to solve the angle :/

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.0put cos x =y, then you get a quadratic in y..

ashwinjohn3
 3 years ago
Best ResponseYou've already chosen the best response.1But \[1=\cos ^{2}x+\sin ^{2} x\] =\[\sin ^{2}x+\cos ^{2}x3\cos ^{2}x=\sin ^{2}x2\cos ^{2}x\]

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.0\(3 \sin^2 x  2 = \cos x \\ 13\cos^2x = \cos x \\ 13y^2 =y. \\ 3y^2 +y1=0 \) can you solve this quadratic ?

shaqadry
 3 years ago
Best ResponseYou've already chosen the best response.0yeaaa but by using calculator, the answer is in decimal point. is there any other way i can calculate the angle?

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.0you'll get same answer using any other method, that you got on calculator. whatever you got, equate it to y= ..., ... so, cos x = ... , .... then take cos^{1} (or arccos) of those 2 values ("decimal values"), using calculator, and ou'll get 2 angles.

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.0you might be getting, 0.767 and 0.434 then 2 angles will be cos^{1}(0.767) and cos^{1}(0.434) calculate those using calculator.
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