# how to align equations with some text

I want to align the equations with text. Though the equations are aligned as I want it to be but still the text is not aligned.

\begin{align}
\mathscr{F}^\prime(x_0)^{-1}&\in L(Y,X) \quad &\textrm{for some } x_0\in{D}; \nonumber\\
\big\Vert{\mathscr{F}^\prime(x_0)^{-1}\mathscr{F}(x_0)}\big\Vert&\le {\color{red}\eta} &{}\nonumber
\\
\big\Vert{\mathscr{F}^\prime(x_0)^{-1}\big[\mathscr{F}^\prime(x)-\mathscr{F}^\prime(x_0)\big]}
\big\Vert &\le L_0
\left\Vert{x-x_0}\right\Vert\quad &\textrm{for all } x\in{D}; \nonumber\\
\big\Vert{\mathscr{F}^\prime(x_0)^{-1}\big[\mathscr{F}^\prime(x)-\mathscr{F}^\prime(y)\big]}
\big\Vert &\le L
\left\Vert{x-y}\right\Vert\quad &\textrm{for all } x,y\in{D}; \nonumber\\
h_{AH} = \xoverline{L}_{\eta} &\le \dfrac{1}{2} &{}
\intertext{and}
\xoverline{U}(x_0,\lambda_0) &\subseteq D, &{}\nonumber
\end{align}


Another question: is there any way to write the preceding equations more aesthetically? Thank your response.

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Please add 4 more lines needed (\documentclass{...} to \end{document})to make it compilable MWE so that our wizards can directly copy/paste your code and start work on it. –  percusse Sep 4 '12 at 8:04

You should put the text in the fourth column, which is left aligned:

\documentclass{article}

\usepackage{amsmath,mathrsfs,xcolor,mathtools}

\begin{document}
\begin{align}
\mathscr{F}'(x_0)^{-1}
&\in L(Y,X)
&& \text{for some } x_0\in{D};
\nonumber\\
\lVert\mathscr{F}'(x_0)^{-1}\mathscr{F}(x_0)\rVert
&\le \textcolor{red}{\eta}
\nonumber\\
\lVert\mathscr{F}'(x_0)^{-1}[\mathscr{F}'(x)-\mathscr{F}'(x_0)]\rVert
&\le L_0\lVert x-x_0\rVert
&& \text{for all } x\in{D};
\nonumber\\
\lVert\mathscr{F}'(x_0)^{-1}[\mathscr{F}'(x)-\mathscr{F}'(y)]\rVert
&\le L\lVert x-y\rVert
&&\text{for all } x,y\in{D};
\nonumber\\
h_{AH} = \xoverline{L}_{\eta}
&\le \dfrac{1}{2}
\shortintertext{and}
\xoverline{U}(x_0,\lambda_0)
&\subseteq D,
\nonumber
\end{align}
\end{document}


I've removed all the \big commands (which should be \bigl and \bigr for left and right delimiters, but don't seem necessary here). Instead I used \lVert and \rVert to state precisely the nature of the symbols, whether opening or closing delimiters. The shorthand ' is equivalent to ^{\prime}. Finally, \shortintertext from the mathtools package requires less vertical space than \intertext.

It's not clear what the number refers to, the whole alignment or just the central equation.

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Why are you using \dfrac for the last 1/2 fraction, doesn't \tfrac look better? –  daleif Sep 4 '12 at 9:46
@daleif Possibly, but I like a big fraction better, in alignments; in this case \tfrac may be good for keeping the rythm of the lines. I didn't change that from the original input. –  egreg Sep 4 '12 at 9:51
I usually recommend using \tfrac is the fraction is simple and is the only thing tall on the line –  daleif Sep 5 '12 at 10:12
@egreg: I'm sorry to pester you like this, but I remember once asking you, in a comment, about the difference between \bigl/\bigr and just \big, i.e., when to use the one or the other, but I cannot for the life of me now find that answer you gave (I've searched my own profile's "responses"-tab as well as your username with query \left \bigl). Since this answer touches on the topic as well, could I ask for a reiteration? TIA! :-) –  morbusg Feb 6 '13 at 7:55
\big produces an ordinary symbol, \bigl an opening symbol and \bigr) a closing one. This is relevant for spacing: try \log\big( and \log\bigl( to see the difference. –  egreg Feb 6 '13 at 9:21