Question

Sa se dermine m€R astfel incat sol. Ec.
X^2-5mx+3=0......sa indeplineasca conditia: x1·x2+x1+x2=7

Answer 1

x1·x2 = c/a = 3/1 = 3;
x1+x2 = -b/a = 5m/1 = 5m;
x1·x2 + x1+x2 = 3+5m = 7
m = 4/5

Answer 2

$S=x_1+x_2= \frac{-b}{a} = \frac{-(-5m)}{1} =5m$

$P=x_1x_2= \frac{c}{a} = \frac{3}{1} =3$

$Astfel$ $x_1x_2+x_1+x_2=7 =\ \textgreater \ S+P=7=\ \textgreater \ 5m+3=7=\ \textgreater \ 5m=4=\ \textgreater \ m=$$\frac{4}{5}$