If $$\frac{\cos \theta}{1 - \sin \theta} + \frac{\cos \theta}{1 + \sin \theta} = 4$$, find the value of $$\theta$$, where $$\theta$$ is acute.

$$\frac{\cos \theta}{1 - \sin \theta} + \frac{\cos \theta}{1 + \sin \theta}=4 $$,

$$\frac{{\cos \theta}\times{(1 + \sin \theta)} + {\cos \theta}\times{(1 - \sin \theta)}}{1-\sin \theta^2} = 4$$,

$$\frac{{\cos \theta}\times{(1 + \sin \theta)} + {\cos \theta}\times{(1 - \sin \theta)}}{\cos \theta^2} = 4$$,

$$\frac{{(1 + \sin \theta)}+ {(1 - \sin \theta)}}{\cos \theta} = 4$$,

$$\frac{2}{\cos \theta} = 4$$,

$$\frac{2}{4} = {\cos \theta}$$,

$$\frac{1}{2} = {\cos \theta}$$,  

$$ \theta $$ = 60$$ ^{\circ}$$