Réponses

2013-11-01T16:02:05+01:00
A=(7x+4)²+(x-3)²
A=(x²+2*7x*4+4²)+(9x²-9x*3*2+3²), A=7x²+42x+16+9x²-54x+9, A=16x²-12x+25
B=9x(x-9)-(7x+2)²
B=(9x*x-9x*9)-(7x²+2*7x*2+2²), B= 9x²-81x-7x²+28x+4, B=2x²-53x+4