0 1 - 1 1 = -1 0
det 0 1 =0-(-1)=1
-1 0
b) AxA= ( 1 1 ) X ( 1 1)= ( 1 2)
0 1 0 1 0 1
BXB =( 1 0) x ( 1 0) = 1 0
1 1 1 1 2 1
C=AxA+BXB=Răspuns:
Explicație pas cu pas:
a)
( 1 1 ) ( 1 0) 0 1
0 1 - 1 1 = -1 0
det I 0 1 I =0-(-1)=1
-1 0
b) AxA= ( 1 1 ) X ( 1 1)= ( 1 2)
0 1 0 1 0 1
BXB =( 1 0) x ( 1 0) = 1 0
1 1 1 1 2 1
C=AxA+BXB= 1 2 + 1 0 = 2 2
0 1 2 1 2 2
det C=2x2-2x2=0 ⇒ matricea C nu e inversabila
c) 1 1 + 1 2 = 1+x 2+y
0 1 x y x y
1 2 + 1 0 = 3 2
x y 1 1 x+y y
1+x 2+y =3 2 ⇒ 1+x=3 ⇒ x=2
x y x+y y 2+y=2 ⇒y=0
