Question

simplificati fractia algebrica x^2-6x+8 supra 4-x^2

Answer 1

 (x^2-6x+8)/(4-x^2)

x^2-6x+8=x^2-2x-4x+8=x(x-2)-4(x-2)=(x-2)(x-4)

4-x^2=(2-x)(2+x)=-(x-2)(x+2)

Fractia noastra devine:

 (x^2-6x+8)/(4-x^2)=

=[(x-2)(x-4)]/[-(x-2)(x+2)]=

simplificam prin x-2 :

(x-4)/[-(x+2)]=(4-x)/(2+x)