Let A=⎛⎜⎝100210321⎞⎟⎠ , If μ1 and μ2 are column matrices such that Aμ1=⎛⎜⎝100⎞⎟⎠ and Aμ2=⎛⎜⎝010⎞⎟⎠, then μ1+μ2 is equal to:
⎛⎜⎝−110⎞⎟⎠
⎛⎜⎝−11−1⎞⎟⎠
⎛⎜⎝−1−10⎞⎟⎠
⎛⎜⎝1−1−1⎞⎟⎠
A(μ1+μ2)=⎡⎢⎣110⎤⎥⎦ Now |A|=1 A−1=1|A|adj A μ1+μ2=A−1⎡⎢⎣110⎤⎥⎦=⎡⎢⎣100−2101−21⎤⎥⎦⎡⎢⎣110⎤⎥⎦=⎡⎢⎣1−1−1⎤⎥⎦