Question

Dada a matriz A = [aij]2x3, sendo aij=i + j e dada a matriz B=[bij] 2x3, com bij = i+3j, qual a soma dos algarismos a23 e b13? 

A) 9
B) 10
C) 12
D) 15
E) 14 ​

Answer 1

A = [a11 a12 a13]

[a21 a22 a23]

aij = i + j

a11 = 1 + 1 = 2

aij = i + j

a21 = 2 + 1 = 3

aij = i + j

a12 = 1 + 2 = 3

aij = i + j

a22 = 2 + 2 = 4

aij = i + j

a13 = 1 + 3 = 4

aij = i + j

a23 = 2 + 3 = 5

B = [b11 b12 b13]

[b21 b22 b23]

bij = i + 3j

b11 = 1 + 3 . 1 = 1 + 3 = 4

bij = i + 3j

b21 = 2 + 3 . 1 = 2 + 3 = 5

bij = i + 3j

b12 = 1 + 3 . 2 = 1 + 6 = 7

bij = i + 3j

b22 = 2 + 3 . 2 = 2 + 6 = 8

bij = i + 3j

b13 = 1 + 3 . 3 = 1 + 9 = 10

bij = i + 3j

b23 = 2 + 3 . 3 = 2 + 9 = 11

a23 + b13 = 5 + 10 = 15