Implementing a digital resonator using matlab

Good morning to all...I have a problem. I want to build a digital resonator on Matlab, with a sampled frequency response given by: T(f) = (A) / (1 - Bz^(-1) - Cz^(-2))...z=exp(j 2 PI f T), f is the frequency in Hz and ranges from 0 to 5 kHz. This resonator is also used as low pass filter, setting the frequency to 0. Which are the commands that I have to use to implement this resonator?

[Micaela]

I have made simply

b = [A];

a = [1 -1*B -1*C];

y = filter(b, a, x);

But I think it is not correct.

[Jagdish Chandra]

b = [A 0 0];

a = [1 -B -C];

sys = tf(b,a);

f = 0:5000;

z=exp(j*2*pi*f*t);

t = 0:0.01:5; % you"ll have to vary t as well

lslim(sys,z,t), % output response of any input z,t with respect to sys;