Respuesta :
Draw a triangle: QUADRANT 2 since tan(θ) is less than 0.
Sides: 1, 2√2, 3 (PYTH. THEOREM)
cos(θ)= (2√2)/3
Sides: 1, 2√2, 3 (PYTH. THEOREM)
cos(θ)= (2√2)/3
If sin theta is 1/3, then theta is in either QI or Q2. If tan theta is negative, then theta is in either Q2 or Q4. Thus, theta is in Q2.
If sin theta = opp / hyp = 1/3, then opp=1 and hyp=3. Thus, adj=sqrt(3^2-1^2), or sqrt 8, or 2sqrt 2.
Then cos theta = adj / hyp = 2sqrt(2) / 3.
If sin theta = opp / hyp = 1/3, then opp=1 and hyp=3. Thus, adj=sqrt(3^2-1^2), or sqrt 8, or 2sqrt 2.
Then cos theta = adj / hyp = 2sqrt(2) / 3.