SOLUTION: If cos(theta) = -0.6 and sin(theta) is greater than 0, find the exact value of tan(theta) + sin(theta)

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Question 1127162: If cos(theta) = -0.6 and sin(theta) is greater than 0, find the exact value of tan(theta) + sin(theta)
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The cos is negative in both the
2nd and 3rd quadrants
--------------------------
Between these two, the sin is
positive in the 2nd quadrant
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If +cos%28+theta+%29+=+-.6+ then
+%28+-.6+%29%5E2+%2B+%28+.8+%29%5E2+=+1%5E2+
+.36+%2B+.64+=+1+, so
+sin%28+theta+%29+=+.8+
+tan%28+theta+%29+=+.8%2F%28-.6%29+
+tan%28+theta+%29+=+-4%2F3+
----------------------------
+tan%28+theta+%29+%2B+sin%28+theta+%29+=+-4%2F3+%2B+4%2F5+
+tan%28+theta+%29+%2B+sin%28+theta+%29+=+-20%2F15+%2B+12%2F15+
+tan%28+theta+%29+%2B+sin%28+theta+%29+=+-8%2F15+
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check the math