- = . Introduce new variable y = csc(2x). Then your equation takes the form = . Factor it: (y+1)*(y-2) = 0 The solutions are y = -1 and y = 2. Now you need to solve two equations: 1) csc(2x) = -1 -----> = -1 -----> sin(2x) = -1 -----> 2x = 270° -----> x = 135°. 2) csc(2x) = 2 -----> = 2 -----> sin(2x) = -----> 2x = 30° and 2x = 150° -----> x = 15° and x = 75°. Answer. The solutions are x = 15°, x = 75° and x = 135°.
------- Converting from csc to sin
---------- Multiplying by LCD,
[2 sin (2x) - 1][sin (2x) + 1] = 0 ------ Factoring trinomial
2 sin (2x) – 1 = 0 AND sin (2x) + 1 = 0
2 sin (2x) = 1 AND sin (2x) = 0 - 1
AND sin (2x) = - 1
AND
30 = 2x AND 270 = 2x
(Q I) AND (Q II)
(Q II)
No INTERVAL was stated (the likes of:) so these are the 3 solutions