Answer:
Part a)
Part b)
Part c) (s+t) lie on Quadrant IV
Step-by-step explanation:
[Part a) Find sin(s+t)
we know that
step 1
Find sin(s)
we have
substitute
---> is positive because s lie on II Quadrant
step 2
Find cos(t)
we have
substitute
is negative because t lie on II Quadrant
step 3
Find sin(s+t)
we have
substitute the values
Part b) Find tan(s+t)
we know that
tex]tan(s + t) = (tan(s) + tan(t))/(1 - tan(s)tan(t))[/tex]
we have
step 1
Find tan(s)
substitute
step 2
Find tan(t)
substitute
step 3
Find tan(s+t)
substitute the values
Part c) Quadrant of s+t
we know that
----> (s+t) could be in III or IV quadrant
----> (s+t) could be in III or IV quadrant
Find the value of cos(s+t)
we have
substitute
we have that
-----> (s+t) could be in I or IV quadrant
----> (s+t) could be in III or IV quadrant
----> (s+t) could be in III or IV quadrant
therefore
(s+t) lie on Quadrant IV