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Could someone please help me solve this problem, please show evidence of the answer, process

Could someone please help me solve this problem, please show evidence of the answer-example-1
User Teekkari
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1 Answer

6 votes

Answer:


\tan \theta=-(√(5))/(2)


\cos \theta=(2)/(3)


\sin \theta=-(√(5))/(3)

Explanation:

To find the exact values of the trigonometric functions of θ, we can use the following trigonometric identities:


\boxed{\begin{minipage}{4 cm}\underline{Trigonometric Identities}\\\\$\sec x=(1)/(\cos x)$\\\\\\$\tan x=(\sin x)/(\cos x)$\\\\\\$\sin^2x+\cos^2x=1$\\\end{minipage}}

In quadrant IV, cosine of the angle is positive, whereas sine of the angle is negative.

Given that sec θ = 3/2, and secant is the reciprocal of cosine:


\sec \theta=(3)/(2)


(1)/(\cos \theta)=(3)/(2)


\boxed{\cos \theta=(2)/(3)}

To find sin θ, we can substitute the found value of cos θ into the Pythagorean identity:


\sin^2 \theta+\cos^2 \theta=1


\sin^2 \theta+\left((2)/(3)\right)^2=1


\sin^2 \theta=1-\left((2)/(3)\right)^2


\sin \theta=\sqrt{1-\left((2)/(3)\right)^2}


\sin \theta=(√(5))/(3)

As sine of the angle is negative in quadrant IV:


\boxed{\sin \theta=-(√(5))/(3)}

Finally, substitute the values of sin θ and cos θ into the tan θ identity to find tan θ:


\tan \theta=(\sin \theta)/(\cos \theta)


\tan \theta=(-(√(5))/(3))/((2)/(3))


\boxed{\tan \theta=-(√(5))/(2)}

Therefore, the exact values of the trigonometric functions for θ are:


\tan \theta=-(√(5))/(2)


\cos \theta=(2)/(3)


\sin \theta=-(√(5))/(3)

User OTTA
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