Bonjour,
a. 3/2x (5/4x + 4)
= 3/2x * 5/4x + 3/2x * 4
= (3 * 5)/(2 * 4)x² + (3 * 4)/2x
= 15/8x² + 12/2x
= 15/8x² + 6x
b. 5/3x² + 10/7x
= 5x * (1/3x + 2/7)
c. 1/x + 1/(x + 2)
= [tex]\frac{x +2}{x(x+2)} +\frac{x}{x(x+2)} =\frac{x+2+x}{x(x+2)} =\frac{2x +2}{x(x+2)}[/tex] pour x ≠ 0 et x ≠ -2
d. [tex]\frac{1}{x+3} -\frac{1}{x} = \frac{x}{x(x+3)} -\frac{x+3}{x(x+3)} = \frac{x - x - 3}{x(x+3)} =\frac{-3}{x(x+3)}[/tex] pour x ≠ 0 et x ≠ -3
