```
C_1 = 0.5; C_2 = 0.8; C_3 = 0.4; C_5 = 0.3;
cvx_begin
variable A
minimize( (C_1.*(1 - A)).*(2.^(C_2./(1 - A)) - 1) + (C_3.*A).*(2.^(C_4./A) - 1))
subject to
0 < A < 1;
cvx_end
```

I have the above convex optimization problem but the following error appears.

Error using .* (line 173)

Disciplined convex programming error:

Cannot perform the operation: {positive constant} ./ {real affine}

Error in ./ (line 19)

z = times( x, y, β./β );

I tried to fix it after reading the division rule but still cannot figure out what is wrong