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Find the values of the trigonometric functions of ∅ from the information given.tan(∅) = -2, sin(∅) > 0

Find the values of the trigonometric functions of ∅ from the information given.tan-example-1
User Voxter
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18 votes

Solution


\tan \emptyset=-2,\sin \emptyset>0

Call tan ∅ = t = -2, Use the trig identity:


\cos ^2\emptyset=(1)/(1+t^2)

Since tan ∅ = -3 is negative and sin ∅ > 0, then ∅ should be in quadrant II


\begin{gathered} \cos ^2\emptyset=(1)/(1+4)=(1)/(5)=0.2 \\ \cos ^2\emptyset=0.2 \\ \cos \emptyset=-0.45 \end{gathered}
\begin{gathered} \sin ^2\emptyset=1-\cos ^2\emptyset=1-0.2=0.8 \\ \sin ^2\emptyset=0.8 \\ \sin \emptyset=0.89,\text{ }\mleft(QuadrantII\mright) \end{gathered}
\cot \emptyset=-(1)/(2)
co\sec \emptyset=(1)/(\sin\emptyset)=(1)/(0.894)=1.12
\sec \emptyset=(1)/(\cos\emptyset)=(1)/(-0.447)=-2.24

User Davena
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