f=12πk1−k2m\rm{f=\dfrac{1}{2 \pi} \sqrt{\dfrac{k_{1}-k_{2}}{m}}}f=2π1mk1−k2
f=12πmk1+k2\rm{f=\dfrac{1}{2 \pi} \sqrt{\dfrac{m}{k_{1}+k_{2}}}}f=2π1k1+k2m
f=12πmk1−k2\rm{f=\dfrac{1}{2 \pi} \sqrt{\dfrac{m}{k_{1}-k_{2}}}}f=2π1k1−k2m
f=12πk1+k2m\rm{f=\dfrac{1}{2 \pi} \sqrt{\dfrac{k_{1}+k_{2}}{m}}}f=2π1mk1+k2