Question

fie expresia F(x)=(1/x-1-x+x^2/x^3-2x+1)÷x+1/x-1 unde x apartine luiR/{-1,1}. a)sa se arate ca x^3-2x+1=(x-1)(x^2+x-1)

Answer 1

x³-2x+1=

= x³-x-x+1

=x(x²-1)-(x-1)

=x(x-1)(x+1)-(x-1)

=(x-1)[x(x+1)-1]

=(x-1)(x²+x-1)