How to calculate $\lim\limits_{i\to\infty} \frac{5^i - 2^{3i+1}}{7^{i-2}+8^i}$? I'm having trouble finding the answer to the limit 
$$\lim\limits_{i\to\infty} \dfrac{5^i - 2^{3i+1}}{7^{i-2}+8^i}$$

I get the answer 98, which to me seem to be wrong. Can someone help me?
Thanks in advance.

Thanks everyone 
got it 
$a_i = \frac{5^i - 2^{3i+1}}{7^{i-2}+8^i}$
            $$=\lim_{i\to\infty}\frac{5^i-2(8^i)}{7^i\cdot7^{-2}+8^i}\cdot\frac{\frac{1}{8^i}}{\frac{1}{8^i}}=\lim\limits_{i\to\infty} -2= -2 $$
