Question 920583
Suppose sin u = - 2/9 and tan u < 0.
given data shows reference angle u is in quadrant IV where sin<0, cos>0
cos u=&#8730;(1-sin^2 u)=&#8730;(1-4/81)/&#8730;(77/81)=&#8730;77/9
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a. Locate the terminal point Pu for u on the unit circle and find its coordinates.
P(u)=(-2/9,&#8730;77/9)
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b. Find the exact value of each of the following:
i. cos (74&#960; – u)=cos u
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ii. tan (u + 3&#960;/2)=2&#960;-u=-tan u
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iii. csc (-u )=1/sin (-u)=1/-sin u=-csc u