Question

Sa se determine parametrii pentru care operatiile date au elementul neutru indicat:
b) M=Q,x compus y=x+y+a, e= -5;
c) M=(2,3), x compus y=(5xy-12x-12y+a)/(2xy-5x-5y+13), e=5/2.

Answer 1

Răspuns:

Explicație pas cu pas:

xoy=x+y+a

y=-5

xo(-5)=x-5+a=x

-5+a=0

a=5

Revin       imediat

______________________________

xoy=(5xy-12x-12y+a)/(2xy-5x-5y+13)

e=5/2

xo5/2=(5x*5/2-12x-12*5/2+a)/(2x*5/2-5x-5*(5/2)+13)=x
25x/2-12x-60/2+a)/10x/2-5x-25/2+13=x

25x-24x-60+2a)/(10x_10x-50+26=x

X-60+2a)/(-24)=x

x-60+2a=-24x

x+24x-60+2a=0
25x-60+2a=0
Cred      ca    e     gresita   x    ar    fi  trebuit      sa    dispara
Continui         asa

x=2

25*2-60+2a=0

50-60+2a=0

-10+2a=0

a=     -5
X=3

25*3-60+2a=0
75-60+2a=0
15+2a=0

a= -15/2
=>

a∈(-5,-15/2)