Bonjour
Factoriser -14xau carré +23x-21
-14x^2 + 23x - 21
= -(14x^2 - 23x + 21)
= -[(xV14)^2} - 2 * xV14 * 23/V14 + (23/V14)^2 - (23/V14)^2 + 21]
= -[(xV14 - 23/V14)^2 - 529/14 + 294/14]
= -[(xV14 - 23/V14)^2 - 235/14]
= -[(xV14 - 23/V14 - V(235/14))(xV14 - 23/V14 + V(235/14))
