Cormen Edition 3 Exercise 4.4 Question 9 (Page No. 93)

Question

Use a recursion tree to give an asymptotically tight solution to the recurrence $T(n)=T(\alpha n) +T((1-\alpha)n) +cn$,where $\alpha$ is a constant in the range $0<\alpha<1$ and $c>0$ is also constant.