Question

va rog ajutatima va implor plssaa

Answer 1

a) a=1; b=-8; c=7
∆=b²-4ac=64-4·1·7=64-28=36
X1,2=( -b±√∆ ) / 2a =(8±√36)/2= (8±6)/2
X1=(8+6)/2=14/7=7
X2=(8-6)/2=2/2=1

B)a=2; b=-1; c=-1
∆=b²-4ac=1-4·2·(-1)=1+8=9
X1,2=( -b±√∆ ) / 2a =(1±√9)/2·2= (1±3)/4
X1=(1+3)/4=4/4=1
X2=(1-3)/4=-2/4=-1/2

C)a=-1; b=6; c=-8
∆=b²-4ac=36-4·(-1)·(-8)=36-32=4
X1,2=( -b±√∆ ) / 2a =(-6±√4)/2·(-1) = (-6±2)/-2
X1=(-6+2)/-2=-4/-2=2
X2=(-6-2)/-2=-8/-2=4

D) a=6; b=1; c=-2
∆=b²-4ac=1-4·6·(-2)=1+48=49
X1,2=( -b±√∆ ) / 2a =(-1±√49)/2·6= (-1±7)/12
X1=(-1+7)/12=6/12=1/2
X2=(-1-7)/12=-8/12=-2/3

E) a=-1; b=5; c=-6
∆=b²-4ac=25-4·(-1)·(-6)=25-24=1
X1,2=( -b±√∆ ) / 2a = (-5±√1)/2·(-1)= (-5±1)/-2
X1=(-5+1)/-2=-4/-2=2
X2=(-5-1)/-2=-6/-2=3

F) =-2; b=-1; c=-3
∆=b²-4ac=1-4·(-2)·(-3)=1-24=-23
∆<0 ; Ecuația nu are soluții reale.