solve : Given T(1) =1
$T(n) = 8T(\frac{n}{2}) + n^2$
$T(\frac{n}{2}) = 8T(\frac{n}{2^2}) + (\frac{n}{2})^2$
$T(\frac{n}{2^2}) = 8T(\frac{n}{2^3}) + (\frac{n}{2^2})^2$
$T(\frac{n}{2}) = 8^2T(\frac{n}{2^3}) + 8(\frac{n}{2^2})^2 +(\frac{n}{2})^2$
Now, T(n) = $8^3T(\frac{n}{2^3}) + 8^2(\frac{n}{2^2})^2 + 8(\frac{n}{2})^2 +(\frac{n}{2^0})^2$
now i always stuck after this help plz , now when we check that which series is forming we have to take $8^3T(\frac{n}{2^3})$
seperate from $8^2(\frac{n}{2^2})^2 + 8(\frac{n}{2})^2 +(\frac{n}{2^0})^2$ and then check whic series is formed by $8^2(\frac{n}{2^2})^2 + 8(\frac{n}{2})^2 +(\frac{n}{2^0})^2$
or we have to take whole $8^3T(\frac{n}{2^3}) + 8^2(\frac{n}{2^2})^2 + 8(\frac{n}{2})^2 +(\frac{n}{2^0})^2$