Question

Se considera expresia E (x)=(2x-8supra x la puterea a doua -8x +15 -1 supra x-3):1supra x la puterea a doua -25

Answer 1

x²-8x+15=0
Δ=64-60=4
x₁=(8-2)/2=6/2=3
x₂=(8+2)/2=10/2=5
E(x)=[(2x-8)/(x²-8x+15)-1/(x-3)]:1/(x²-25)
E(x)=[(2x-8)/(x-3)(x-5)-1/(x-3)]:1/(x-5)(x+5)
E(x)={[(2x-8)-(x-5)]/(x-3)(x-5)}·(x-5)(x+5)=simplif cu x-5
E(x)={[(2x-8-x+5)]/(x-3)}·(x+5)
E(x)=[(x-3)/(x-3)]·(x+5)
E(x)=x+5