Question 24931
n to the power of 4 + 8n to the power of 3 + 15n to the power of 2 
I assume you have to solve for n ?
First put the expression =0 so now we have an eqation
{{{n^4+8n^3+15n=0}}}
look for common factor,in this case {{{n^2}}}
take this out to get
{{{n^2(n^2+8n+15)=0}}}expression within brackets factorises easily to give
{{{n^2(n+3)(n+5)=0}}}
take n+3=0
so n=-3
n+5=0
n=-5
so your answer is n=-3 and n=-5
try plugging these into original equation to check
hope this helps
Pete