[texhax] Changing spacing between some lines in multline etc

[Victor Ivrii]

1) Sometimes I am not happy with some vertical spacing between two
particular lines in "equations" containing more than two lines (for
two lines {spreadlines} of mathtools takes care but if there are more
than two lines it affects all spacing). Is there any regular method
(except increasing spacing by including phantoms)?

2) Sometimes I want to use a kind of multline but with all equations
except the first one flashed right. I cannot invent anything except
some ugly games with {align}. Is there a better solution?

3) sometimes I want to use \sum\int   as a single big operator, so the
subscript would be strictly below their middle. Is there a way?

Thank you in advance

              Victor

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Victor Ivrii, Professor, Department of Mathematics, University of Toronto
http://www.math.toronto.edu/ivrii