Answer:
cos Ф = adj / hyp = √5 / 3
Step-by-step explanation:
If sin Ф is +, then Ф must be in either Quadrant 1 or Quadrant 2.
If tan Ф < 0, then Ф must be in either Quadrant 2 or Quadrant 3.
So we conclude that Ф is in Quadrant 2.
If sin Ф = opp / hyp = 2/3, then opp = 2 and hyp = 3, and adj is found using the Pythagorean Theorem:
adj = √( 3² - 2² ) = √( 5 )
With adj = √5 and hyp = 3, cos Ф = adj / hyp = √5 / 3
