wyznacz siny xxx: wyznacz sin y, jeśli wiesz, że sin(x−y)+sin9x+y)=1/2, sinx=1/3, y∊(3/2π,2π)

M:

Bo_ra: sin(x−y)=sin(x)cos(y)−cos(x)sin(y) sin(x+y)=sin(x)cos(y)+cos(x)sin(y)

	1
sin(x−y)+sin(x+y)=
	2

	1
sin(x)cos(y)−cos(x)sin(y)+(sin(x)cos(y)+cos(x)sin(y)=
	2

	1
2sin(x)cos(y)=
	2

	1
sin(x)cos(y)=
	4

	14
cos(y)=
	sin(x)

	3
cos(y)=		(na plusie
	4

	√7
sin(y)=−√1−cos2(y)=−
	4

−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−

	2√2
cos(x)=√1−sin2(x)=
	3