If f(x) is continuous at x = 0 where
\(f\left( x \right) = \frac{{1 - \;\cos kx}}{{{x^2}}}\;for\;x \ne 0\)
\(f\left( x \right) = \frac{1}{4}\;for\;x = 0\)
then what is the value of k?1
\(\frac{1}{{\surd 2}}\)
2
\(- \frac{1}{{\surd 2}}\)
3
\(\pm \frac{1}{{\surd 2}}\)
4
\(\frac{1}{2}\)