1 Long Equations Here is a long equation without line number. Z Z Θ(fε (t)) dµ(t) = − fε4 (t) dµ(t) G G Z Z 2 2 2 2 + (b + 2a ) fε (t) dµ(t) + a2 b2 − a4 . fε (t) dµ(t) + 2ab G G Here is the same long equation with a single equation number. The ”notag” is used to suppress numbering the first line. Z Z Θ(fε (t)) dµ(t) = − fε4 (t) dµ(t) G G Z Z + (b2 + 2a2 ) fε2 (t) dµ(t) + 2ab2 fε (t) dµ(t) + a2 b2 − a4 . (1) G G Here is the same long equation with a single equation number, but centered. Here the combination of ”equation” and ”split” environments is used. We prefer this version for numbered long equations. Z Z Θ(fε (t)) dµ(t) = − fε4 (t) dµ(t) G G Z Z (2) 2 2 2 2 + (b + 2a ) fε (t) dµ(t) + 2ab fε (t) dµ(t) + a2 b2 − a4 . G 2 G Multiline Equations Example 1. Here is a string of equations typeset with gather. Z π Z π 1 1 an = f (x)e−inx dx = f0 (x)e−inx dx 2π −π 2π −π Z π Z π Z ∞ 1 1 e−inx −inx = lim fδn (x)e dx = lim gδn (t) dx dt 1−α n→∞ 2π −π n→∞ 2π −∞ −π |x − t| Z π 1 = U µ (x)e−inx dx. 2π −π α Here is the same set of equations typeset with align. Z π Z π 1 1 an = f (x)e−inx dx = f0 (x)e−inx dx 2π −π 2π −π Z π Z π Z ∞ 1 1 e−inx = lim fδn (x)e−inx dx = lim gδn (t) dx dt 1−α n→∞ 2π −π n→∞ 2π −∞ −π |x − t| Z π 1 = U µ (x)e−inx dx. 2π −π α 1 Each of these two versions has advantages over the other. The first looks better on the page while the second highlights the fact that a formula for an is underway. The second formulation introduces an ”overfill” on the second line, however, so must be altered to fit on the page properly. Here is a reformulation. Z π Z π 1 1 f (x)e−inx dx = f0 (x)e−inx dx an = 2π −π 2π −π Z π 1 = lim fδn (x)e−inx dx n→∞ 2π −π Z π Z ∞ 1 e−inx = lim gδn (t) dx dt 1−α n→∞ 2π −∞ −π |x − t| Z π 1 = U µ (x)e−inx dx. 2π −π α We prefer this third version. Example 2. Here is a common alignment first without line number, then with. X qj N 0 P (GN ) ≤ P kBj kT > 4 T µ 2 ≤ <j≤µ X µ 2 <j≤µ 4T 0 3/2 C qj (log pj+1 ) N qj T 4T 0 3/2 C µ (log pµ+1 ) N T 4T CT0 3(µ + 1)l ≤ µ exp , N γ ≤ P (GN ) ≤ X P µ 2 <j≤µ ≤ X µ 2 <j≤µ kBj0 kT qj N > 4 T 4T 0 3/2 C qj (log pj+1 ) N qj T 4T 0 3/2 C µ (log pµ+1 ) N T 4T CT0 3(µ + 1)l ≤ µ exp , N γ ≤ 2 (3) Here is one more example of a numbered multiline equation. 1 e−s e−(hk −1)s e−(hk +1)s e−2hk s + + ··· + − − ··· − hk hk − 1 1 1 hk hX hX k −1 k −1 −js −(2hk −j)s e e = − (4) hk − j hk − j j=0 j=0 Pk (s) = = hk X e−(hk −n)s − e−(hk +n)s . n n=1 3