# [OS X TeX] AMS-LaTeX question

Gary Gray glgray at me.com
Mon May 28 17:20:59 EDT 2012

On May 28, 2012, at 4:04 PM, Michael Sharpe wrote:

>
> On May 28, 2012, at 11:28 AM, Martin Berggren wrote:
>
>>
>> \begin{align*}
>> 	&= \frac{A} { \left( k - m \omega_{0}^{2} \right)^{2} + c^{2} \omega_{0}^{2} } \sqrt{ \left[ \left( k - m \omega_{0}^{2} \right) \left( m \omega_{0}^{2} + k - m \omega_{0}^{2} \right) + c^{2} \omega_{0}^{2} \right]^{2} + \left( m c \omega_{0}^{3} \right)^{2} }
>> 	\\
>> 	&= \frac{A} { \left( k - m \omega_{0}^{2} \right)^{2} + c^{2} \omega_{0}^{2} } \sqrt{ \smash[b]{\underbrace{ \left[ k \left( k - m \omega_{0}^{2} \right) + c^{2} \omega_{0}^{2} \right]^{2} + \left( m c \omega_{0}^{3} \right)^{2} }_{Q}} }.
>> \end{align*}
>>
>> On May 28, 2012, at 19:09 , Gary Gray wrote:
>>
>>> \begin{align*}
>>> &= \frac{A} { \left( k - m \omega_{0}^{2} \right)^{2} + c^{2} \omega_{0}^{2} } \sqrt{ \left[ \left( k - m \omega_{0}^{2} \right) \left( m \omega_{0}^{2} + k - m \omega_{0}^{2} \right) + c^{2} \omega_{0}^{2} \right]^{2} + \left( m c \omega_{0}^{3} \right)^{2} }
>>> \\
>>> &= \frac{A} { \left( k - m \omega_{0}^{2} \right)^{2} + c^{2} \omega_{0}^{2} } \sqrt{ \underbrace{ \left[ k \left( k - m \omega_{0}^{2} \right) + c^{2} \omega_{0}^{2} \right]^{2} + \left( m c \omega_{0}^{3} \right)^{2} }_{Q} }.
>>> \end{align*}
>>
>
> I think this can be improved a bit by adding an invisible \vrule before \smash[b]:
>
> \begin{align*}
> &= \frac{A} { \left( k - m \omega_{0}^{2} \right)^{2} + c^{2} \omega_{0}^{2} } \sqrt{ \left[ \left( k - m \omega_{0}^{2} \right) \left( m \omega_{0}^{2} + k - m \omega_{0}^{2} \right) + c^{2} \omega_{0}^{2} \right]^{2} + \left( m c \omega_{0}^{3} \right)^{2} }
> \\
> &= \frac{A} { \left( k - m \omega_{0}^{2} \right)^{2} + c^{2} \omega_{0}^{2} }\sqrt{\vrule width 0pt depth 5pt\smash[b]{\underbrace{ \left[ k \left( k - m \omega_{0}^{2} \right) + c^{2} \omega_{0}^{2} \right]^{2} + \left( m c \omega_{0}^{3} \right)^{2} }_Q}} .
> \end{align*}
>
> The difference in Computer Modern math at 11pt is small, but can be quite noticeable at some other sizes and with other math fonts. Like other extensible math objects, there is a discrete collection of available sizes that will not produce the same results in all cases.
>
> Michael

Thank you Michael -- that is *perfect*.

Gary