@Carl Love Thanks again i just ended up shifting the frunction across and then shifting the values of the roots back again, but i think i will use this instead. Many thanks again!

@Carl Love 

Thanks that works great! I was just wondering is there away to adapt this so that it finds root that are less than -1??? 

As the function tends to a critical point around -0.8 and therefore i need to take a very large value for N inorder to find roots past this. If i can find the roots past this critical point then i can easily combine them with the roots before hand. Any advice is much appreciated.