Réponses

2012-11-16T23:05:24+01:00

(1-x²)/(x²+1)²=u/(v*w)

 

u'=-2x

v'=2x

w'=2x

 

la dérivé vaut (u'(v*w)-u(v*w)')/(v*w)²

=(-2x(x²+1)²-(1-x²)(4x²))/((x²+1)²)²

=(-2x²(x^4+2x²+1)-(4x²-4x^4))/((x²+1)²)²

=(-2x^6-4x^4-2x²-4x²-4x^4)/((x²+1)²)²

=(-2x^6-8x^4-6x²)/((x²+1)²)²