\(\frac{{\cos \,{\rm{\theta }}}}{{\text{cosec}\,{\rm{\theta }}\, + \,1}}\, + \,\frac{{\cos \,{\rm{\theta }}}}{{\text{cosec}\,{\rm{\theta }}\, - \,1}}\, = \,2\) , 0 < θ < 90°, అయితే sin 4 θ + cos 4 θ విలువ ఎంత?
1
2
2
1
3
\(\frac{1}{2}\)
4
\(\frac{1}{4}\)