Suppose that T is a linear transformation that is not injective. Prove there is a non-zero element u in the domain of T such that T(u) = 0.

Suppose that T is a linear transformation that is not injective. Prove there is a non-zero element u in the domain of T such that T(u) = 0.

Suppose that T is a linear transformation that is not injective. Prove there is a non-zero element u in the domain of T such that T(u) = 0.

Suppose that T is a linear transformation that is not injective. Prove there is a non-zero element u in the domain of T such that T(u) = 0.

Suppose that T is a linear transformation that is not injective. Prove there is a non-zero element u in the domain of T such that T(u) = 0.