scalar multiplication The word"scalar"just means"number"-we use a separate word to distinguish numbers from other mathematical objects we want to calculate with,like matrices. Definition 7.1.2 (scalar multiplication) To multiply a matrix by a scalar,multiply every entry of the matrix by that scalar. a11 入a11 Xain aml .。amn 入am1l 入amn Oλ(4)=(4)4 ⊙(A+4)A=入M+4 OX(A+B)=入A+入B Tongji University】 4/14scalar multiplication . The word ”scalar” just means ”number” – we use a separate word to distinguish numbers from other mathematical objects we want to calculate with, like matrices. . Definition 7.1.2 (scalar multiplication) . . To multiply a matrix by a scalar, multiply every entry of the matrix by that scalar. λ   a11 . . . a1n . . . . . . am1 . . . amn   :=   λa11 . . . λa1n . . . . . . λam1 . . . λamn   .1 λ(µA) = (λµ)A .2 (λ + µ)A = λA + µA 3. λ(A + B) = λA + λB (Tongji University) Linear Algebra 4 / 14