73. let t and t be two linear transformations from r' r". let l,2,., ,} be a basis of r". suppose ths tx;#0 for every i =1, 2,..., n and that x; 1 kerl, io ever

73. Let T and T be two linear transformations from R' R". Let l,2,., ,} be a basis of R". Suppose ths Tx;#0 for every i =1, 2,..., n and that x; 1 Kerl, io every i=1, 2,..., n. Which of the following is/are= necessarily true? (a) Tis invertible (C) Both T and T, are invertible (d) Neither T, nor T, is invetu (b) T2 is invertible eribe ad aE