Let T: R³ R³ be defined by ➜>> 3x, +5x₂-x₂ TX₂ 4x₁-x₂+x₂ 3x, +2x₂-X₁ (a) Calculate the standard matrix for T. (b) Find T(-1,2,4) by definition. [CO3-PO1:C4] (5 marks) [CO3-PO1:C1]