How can I express this problem in CVX?

K=3;

\lambda=[.01\hspace{3mm} .05 \hspace{3mm} .3];

\delta_k=\frac{4}{5}2^{-\frac{b_k}{5}};

I_k=\lambda_k\delta_k;

My optimization problem is

\min_{b_k}\hspace{3mm}\max_{k\in\{1,2,\cdots,K\}}I_k

How to express the objective function in CVX?

I wrote it in CVX as:

cvx_solver sedumi

cvx_begin

variable b(1,K)  


minimize(max(lambda.*((4)/5)*2.^(-b/(5))))



cvx_end

I get the following error

Error using * (line 41)
Inner matrix dimensions must agree.

Error in Main_Program (line 28)
minimize(max(lambda.*((4)/5)*2.^(-b/(5))))

Change the second * to a .* in your objective function.