∑ i = 1 2 ( a + b ) 2 {\displaystyle \sum _{i=1}^{2}(a+b)^{2}} , ( a + b ) 2 {\displaystyle (a+b)^{2}}
( a + b ) 2 = a 2 + b 2 + 2 a b {\displaystyle (a+b)^{2}=a^{2}+b^{2}+2ab}
1 2 {\displaystyle {\frac {1}{2}}}
6 d 2 y / d x + w 2 y = 0 T = 2 π l g d 2 y d t 2 {\displaystyle {\sqrt {6}}d^{2}y/dx+w^{2}y=0T=2\pi {\sqrt {\frac {l}{g}}}{\frac {d^{2}y}{dt^{2}}}}
H2SO4
NH3
H2O <math>1-6\sum {d}^2 \frac {n)^3}-{n}
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