Given, A=[2−4−31]
⇒A2=[2−4−31][2−4−31]
⇒A2=[4+12−8−4−6−312+1]
⇒A2=[16−12−913]
⇒3A2=[48−36−2739] and 12A=[24−48−3612]
∴(3A2+12A)=[72−84−6351]
Adj(3A2+12A)=[51638472]T=[51846372]
If A=[2−4−31] , then Adj(3A2+12A) is equal to:
Held on 2 Apr 2017 · Verified 6 Jul 2026.
[72−63−8451]
[51846372]
[51638472]
[72−84−6351]
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