Question

sa se determine m aparatine lui R a.i functia F : R ->R , F (x) = x^2 - (2m+1)x+3 sa aiba abscisa varfului egala cu 7/2 ( 7 pe 2 )

Answer 1

abcisa, adica x
xV=-b/2a= -(-(2m+1))/2*1=(2m+1)/2
(2m+1)/2=7/2
2m+1=7
2m=6
m=3
as simple as that!!!

Answer 2

Coordonatele V parabolei f. de gradul 2: V( -b/2a; -delta/4a)

f(x) = x^2 - (2m + 1)x - 3
a = 1; b = -(2m + 1); c = -3

Abscisa = x_V = -b/2a
Ordonata = y_V = -delta/4a

-b/2a= 7/2 → -[-(2m+1)]/2*1=7/2 →
-(-2m-1)= 7 → 2m+1=7 → m= 3