NOTE :
(1+x)^8= 8C0 + 8C1 x + 8C2 x^2 +...+ 8C8 x^8
and counting from 1, we have T1, T2, T3, ..., T9 respectively
So Tk=8 choose k-1 (*)
Tk+1 = 8 choose k
the inequality you solved is acutally for Tk+1 > Tk , from which we obtain k<4.5
hence T5>T4>T3>T2>T1
inequality doesn't hold for larger k...