Forkorting
Posted: 27/05-2008 09:45
Jeg har begynt å repetere litt forkorting av rasjonale uttrykk.
Hva gjør jeg galt her
[tex] \frac{1}{3x-3} + \frac{x+3}{x^2-1} + \frac{1}{x+1} [/tex]
[tex] \frac{1}{3(x-1)} + \frac{x+3}{(x-1)(x+1)} + \frac{1}{x+1} [/tex]
[tex] \frac{x+1}{3(x-1)(x+1)} + \frac{3x+9}{3(x-1)(x+1)} + \frac{3(x-1)}{3(x-1)(x+1)} [/tex]
[tex] \frac{x + 1 + 3x + 9 + 3x - 3}{3(x-3)(x+1)} [/tex]
[tex] \frac{7x + 7}{3(x-1)(x+1)} [/tex]
Svaret skal være
[tex] \frac{7}{3(x-1)} [/tex]
Hva gjør jeg galt her
[tex] \frac{1}{3x-3} + \frac{x+3}{x^2-1} + \frac{1}{x+1} [/tex]
[tex] \frac{1}{3(x-1)} + \frac{x+3}{(x-1)(x+1)} + \frac{1}{x+1} [/tex]
[tex] \frac{x+1}{3(x-1)(x+1)} + \frac{3x+9}{3(x-1)(x+1)} + \frac{3(x-1)}{3(x-1)(x+1)} [/tex]
[tex] \frac{x + 1 + 3x + 9 + 3x - 3}{3(x-3)(x+1)} [/tex]
[tex] \frac{7x + 7}{3(x-1)(x+1)} [/tex]
Svaret skal være
[tex] \frac{7}{3(x-1)} [/tex]