4 The angle \(\theta\) satisfies the equation \(\sin \left( \theta + 45 ^ { \circ } \right) = \cos \theta\).
- Using the exact values of \(\sin 45 ^ { \circ }\) and \(\cos 45 ^ { \circ }\), show that \(\tan \theta = \sqrt { 2 } - 1\).
- Find the values of \(\theta\) for \(0 ^ { \circ } < \theta < 360 ^ { \circ }\).