# Math Help - metric space assignment

1. ## metric space assignment

Hello, I need help with this proof please!, my assignment is due on Wednesday morning and I don't know how to prove it ...please see attached, thanks!

2. Here is a strong hint on #1.
See if you can prove the following: $\left( {\forall n} \right)\left[ {\left| {d\left( {a,b} \right) - d\left( {a_n ,b} \right)} \right| < d\left( {a,a_n } \right)} \right]$.

I cannot read the symbols in #2.