Question

Subpunctul b, va rog ​

Answer 1

Răspuns:

Explicație pas cu pas:

calculezi det(M)=$8m^{3} +1+1-2m-2m=8m^{3} -6m+2$

det(M)=0, $4m^{3} -3m+1=0, 4m^{3}-4m+m+1=0, 4m(m^{2} -1)+m+1=0,\\4m(m-1)(m+1)+m+1=0\\(m+1)(4m(m-1)+1)=0\\m+1=0, m=-1,\\4m^{2}-4m+1=0, (2m-1)^{2}=0, m=\frac{1}{2}$