Question

x ^ ( 2) - 3x + ( m - 1) = 0 para que admite nenhuma raiz real?

Answer 1

$x^2-3x+(m-1)=0\ \to\ a=1,\ b=-3,\ c=(m-1)\\\\ \Delta\ \textless \ 0\ \to\ b^2-4ac\ \textless \ 0\ \to\ b^2\ \textless \ 4ac\ \to\ (-3)^2\ \textless \ 4(m-1)\ \to\\\\ \to\ 9\ \textless \ 4m-4\ \to\ 13\ \textless \ 4m\ \to\ \boxed{m\ \textgreater \ \dfrac{13}{4}}$