Question

giúp cho mình câu b thôi nhé mik cảm ơn

 

b) Rút gọn biểu thức \( B \).

Answer 1

`B = (4/(x - 5) + (3x - 1)/(x^2 - 25) - 1/(x + 5)) . (x^2 + 5x)/(x + 4)`

`B = [(4(x + 5))/((x - 5)(x + 5)) + (3x - 1)/((x - 5)(x + 5)) - (x - 5)/((x - 5)(x + 5))] . (x^2 + 5x)/(x + 4)`

`B = (4x + 20 + 3x - 1 - x + 5)/((x - 5)(x + 5)) . (x(x + 5))/(x + 4)`

`B = (6x+24)/((x - 5)(x + 5)) . (x(x + 5))/(x + 4)`

`B = (6(x + 4))/((x - 5)(x + 5)) . (x(x + 5))/(x + 4)`

`B = (6x)/(x - 5)`