Question

plz solve and explain and I will mark it as brainliest​

Answer 1

ANS.

4

SOLUTION

Given A=(1223)A2−kA−I2=0

→A2=(1223)(1223)=(58810)

A2−kA−I2=[58813]−k[1223]−[1001]

=[48812]−k[1223]=0

=[4−k8−k8−2k12−3k]=0

∴4−k=0⇒k=4

12−3k=0⇒k=4  

∴k=4.