Question

Considerando a Matriz A = (aij)2x2, tal que aij = 2i – 5j, calculando X = At − 3A, obtemos a Matriz X:

(a) =[−3−8−1−6]

(b) =[−3−1−8−6]

(c) =[−9−36−3−18]

(d) =[635−912]

(e) =[625−512]

Answer 1

Olá Bengla

A(i,j) = 2i - 5j 

A(1,1) = 2 - 5 = -3  ⇒ -3A(1,1) = 9
A(1,2) = 2 - 10 = -8 ⇒ -3A(1,2) = 24
A(2,1) = 4 - 5 = -1 ⇒ -3A(2,1) = 3
A(2,2) = 4 - 10 = -6 ⇒ -3A(2,2) = 18 

At(1,1) = -3
At(1,2) = -1
At(2,1) = -8
At(2,2) = -6 

B = At - 3A 

B(1,1) = -3 + 9 = 6
B(1,2) = -1 + 24 = 23
B(2,1) = -8 + 3 = -5
B(2,2) = -6 + 18 = 12

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