Template:Lognormal distribution failure rate function

The Lognormal Failure Rate Function
The lognormal failure rate is given by:


 * $$\lambda (t)=\frac{f(t)}{R(t)}=\frac{\tfrac{1}{t\cdot \sqrt{2\pi }}{{e}^{-\tfrac{1}{2}{{(\tfrac{{t}'-{\mu }'}{})}^{2}}}}}{\int_^{\infty }\tfrac{1}{{{\sigma' }}\sqrt{2\pi }}{{e}^{-\tfrac{1}{2}{{(\tfrac{x-{\mu }'}{{{\sigma' }}})}^{2}}}}dx}$$

As with the reliability equations, standard normal tables will be required to solve for this function.