plot common region which corresponds to some negative value

Dear friends, I am trying to plot the region (on z1-z2 plane) which corresponds to C1 least negative and C2 least negative. If there is no negative values in the C2 vector, then choose the points for which C2==0.

Where

C1= z1*(15*a1 + 5*a2 +a2*z2 – v1);

C2= z2*a2(v2 + z1);

k=1:800; Ts=25e-6

v1=100*sin(100*pi*Ts*k ); 

v2=10* sin(100*pi*Ts*k );

The values of z1 and z2 spread over the x-y plane. They can be any real value. We havefour possible inputs as follow:

a1  a2

0  0

0  1

1  0

1  1

I expecting to see the common region which corresponds to all negative values of the two functions.

Thanks in advance

[KSSV]

What is v1, v2 in C1, C2 ?

[Hamza Makhamreh]

V1 and V2 are sinusoidal functions given in the question. They are the same as v1 and v2.