Ответ:

  1. При \(x=4\): \(3-1.5\cdot4=3-6=-3\).

  2. При \(x=-2\): \(3-1.5\cdot(-2)=3+3=6\).

  3. При \(x=-\frac{1}{3}\): \(3-1.5\cdot\left(-\frac{1}{3}\right)=3+0.5=3.5\).

  4. При \(x=0.8\): \(3-1.5\cdot0.8=3-1.2=1.8\).

Ответ: −3; 6; 3,5; 1,8.