Question 338667
Use the FOIL method,
{{{(v+1/3)(v+1/5)=v^2+(1/5)v+(1/3)v+1/15}}}
{{{(v+1/3)(v+1/5)=v^2+(3/15)v+(5/15)v+1/15}}}
{{{(v+1/3)(v+1/5)=v^2+(8/15)v+1/15}}}