$$\cos \theta =-\frac{1 }{ 5 } and \tan \theta 0, find \sin \theta $$

Question

$$\cos \theta =-\frac{1 }{ 5 } and \tan \theta > 0, find \sin \theta $$

mathstudent55 · Answer

This figure shows in which quadrants the sine, cosine and tangent are positive or negative.
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mathstudent55 · Answer

Look at your give info.
Which quadrant is the answer in?

anonymous · Answer

a.) 4/5
b.) -4/5
c.) $$2\sqrt{6}/5$$
d.) $$-2\sqrt{6}/5$$

mathstudent55 · Answer

-1/5 is a negative number so the cos is negative.
tan theta > 0 means the number is positive so the tan is positive.

mathstudent55 · Answer

We know we have a negative cosine and a positive tangent.
Which quadrant are we dealing with?

anonymous · Answer

quad 3

mathstudent55 · Answer

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Correct!

anonymous · Answer

so sin is negative?

mathstudent55 · Answer

From that we know the sin is negative. Correct.

mathstudent55 · Answer

Ok.
Now we use a triangle.

anonymous · Answer

that would leave us with B and D then right? cuz those are both negative

mathstudent55 · Answer

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