1. Verifique se as transformações abaixo são lineares

(a) T : \mathbb{R}^3 \to \mathbb{R}, T (x, y, z) = x + 5y - z;

(b) T : \mathbb{R}^3 \to \mathbb{R}, T (x, y, z) = x + 5y - z + 1;

(c) T : \mathbb{R}^3 \to \mathbb{R}, T (x, y, z) = x^2 + 5y - z;

(d) T : P_n(t) \to P_n(t), T (p) = p' + p'';