Solve for y 11 sin^2y=13-sin^2y where 0

The first step is to isolate (sin y)^2 to the left side. For
this reason, we'll add (sin y)^2 both sides:

11 (sin y)^2 + (sin
y)^2 = 13

12 (sin y)^2 =13

We'll divide
by 12:

(sin y)^2 = 13/12

sin y = sqrt
(13/12)

But sqrt (13/12)>1 and -sqrt (13/12) < -1,
which is impossible because the limit values of the sine function are -1 and
1.

So, there are no angles to satisfy the given
equation, or, more precise, the equation has no solution.