Question

Potrzebne na już! Znajdź X : 3/x^2-1 + x/x-1 = 11-x/x+1

Answer 1

 zał.  (x-1)(x+1)≠0

     x∈R\{-1 , 1}

 

 

3           x             11-x

------- +  -------  =   ---------                  /*(x-1)(x+1)

x²-1       x-1           x+1

 

3 + x(x+1) = (11-x)(x-1)

3  + x² + x = 11x - 11-x² + x

x² + x² + x -11x-x+3+11 = 0

2x²-11x + 14 = 0

Δ=b²-4ac = 121 -112 = 9         √Δ =3

x1=(-b-√Δ)/2a = (11-3)/4 = 8/2=2

x2 = (-b+√Δ)/2a = (11+3)/4 = 3  1/2

 

odp:

x= 2  U   x = 3  1/2

Answer 2