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Pls solve the following math from trigonometry ​

Pls solve the following math from trigonometry ​-example-1
User Corristo
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1 Answer

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17 votes

Explanation:


\tan(2x) = 1.5

Take the arc tangent,


\tan {}^( - 1) ( \tan(2x) ) = \tan {}^( - 1) (1.5)


2x = 56.3


x = 28.15

b.


(3 \cos(x) + 1)(2 \cos(x) + 3) = - 2


6 \cos {}^(2) (x) + 11 \cos(x) + 3 = - 2


6 \cos {}^(2) (x) + 11 \cos(x) + 5 = 0


6 \cos {}^(2) (x) + 6 \cos(x) + 5 \cos(x) + 5 = 0


6 \cos(x) ( \cos(x) + 1) + 5( \cos(x) + 1) = 0


(6 \cos(x) + 5)( \cos(x) + 1) = 0

Set each factor equal to zero.


6 \cos(x) + 5 = 0


6 \cos(x) = - 5


\cos(x) = - (5)/(6)


x = \cos {}^( - 1) ( (5)/(6) )


x = 146.4

For the second factor,


\cos(x) + 1 = 0


\cos(x) = - 1


x = 180

So the answer for the second one is

146.4 and 180.

User Ante Vrli
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