Introductory Astronomy Question - function help

[Heisenberg.]

The question asks to find a new expression for a function, by substituting suitable expressions for the elimination of lambda and T.
The function is:
b(x)= h^4 * c^3 * U(sub-lambda) / 2*(kT)^5
In this case:
U(sub-lambda)= U(sub-lambda)(lambda,T) - Planck Blackbody Function
x= lambda*k*T / h*c

I assume that there is some way to substitute some of the equations into the function - but I am at loss to see how - any help would be appreciated - Thank You

 

[Redbelly98]

Were you given an expression for U_λ(λ,T)? Perhaps in your textbook or lecture notes ... I think the next step would be to substitute that expression into the RHS of your b(x) equation here.