hey guys,(adsbygoogle = window.adsbygoogle || []).push({});

<n|(a^{-}+a^{+})^4|n> = 5n^{2}+5n+3

I am wondering if some one can show me why left and right side are equal

Thanks in advance

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Bra-ket multiplication

**Physics Forums | Science Articles, Homework Help, Discussion**