Use the substitution method to show that each of the following recurrences defined on the

reals has the asymptotic solution specified. You have to show both the upper $(O)$

and lower $()$ bounds of $T(n).$

a$.T(n)=2T(\frac{n}{3})+(n)$ has solution $T(n)=(n).$

b$.T(n)=4T(\frac{n}{2})+(n)$ has solution $T(n)=(n^2).$