To solve the system means to find the pair of values for x
and y that verifies the equations of the system.
We'll
re-write the second equation of the system, transforming the sum of like trigonometric
functions into a product:
sin a + sin b = 2sin
[(a+b)/2]*cos [(a-b)/2]
sinx + siny = 2sin [(x+y)/2]*cos
[(x-y)/2]
We'll substitute x - y by pi/3 and we'll
get:
sinx + siny = 2sin [(x+y)/2]*cos
[(pi/3)/2](1)
But sinx + siny = sqrt 3
(2)
We'll put (1) = (2):
2sin
[(x+y)/2]*cos [(pi/3)/2] = sqrt 3
We'll divide by
2:
sin [(x+y)/2]*cos [(pi/6)] = (sqrt
3)/2
We'll substitute cos [(pi/6)] =
sqrt3/2
(sqrt3/2)*sin [(x+y)/2] =
sqrt3/2
We'll divide by
sqrt3/2:
sin [(x+y)/2] =
1
(x+y)/2 = arcsin 1
(x+y)/2 =
pi/2
x + y = 2pi/2
x + y = pi
(3)
x - y = pi/3 (4)
We'll add
(3) + (4):
x + y + x - y = pi +
pi/3
We'll combine and eliminate like
terms:
2x = 4pi/3
We'll divide
by 2:
x =
4pi/6
x =
2pi/3
We'll substitute x in
(3):
2pi/3 + y = pi
We'll
subtract 2pi/3 both sides:
y = pi -
2pi/3
y =
pi/3
The solution of the
system is represented by the pair (2pi/3 ; pi/3).
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