Question

1) 2x+1)^2-(2x-1)^2/(x-1)^2-(x+1)^2=-2

2) x^2-2x-15/x^2-10+25=x+3/x-5



Va rog mult

Answer 1

1)(2x+1-2x+1)(2x+1+2x-1) totul supra
(x-1-x-1)(x-1+x+1)=(2×4x)/(-2×2x)=-4x/2x=-2
2)x^2-2x-15=x^2-5x+3x-15=x(x-5)+3(x-5)=(x-5)(x+3)
x^2-10x+25=x^2-5x-5x+25=x(x-5)-5(x-5)=(x-5)^2
(x-5)(x+3) totul supraveghere
(x-5)(x-5) prin simplificare se obține (x+3)/(x-5)