bonjour
A = ( 2 x - x ) / ( x + 1 )
A = x / ( x + 1 )
B = 1 / (x + 1 ) + 1 / x
B = 1 (x) / x ( x + 1) + 1 ( x + 1 ) / x ( x + 1)
B = x / x ( x + 1) + ( x + 1 ) / x ( x + 1 )
B =( x + x + 1 ) / x ( x + 1)
B = 2 x + 1 / x ( x + 1 )
finis la C , tu mets sous 4 x
