Bonjour
1/ Aire du rectangle = (2x+5) ( 3x-4)
6x² - 8x +15x -20
6x² + 7x -20
Aire du carré = (x+2)² = x² +4x +4
Aire de la figure = 6x² -7x -20 + x² +4x +4
7x² -3x -16
2/ A = 3(4x -5)
B = x( 8x +3)
C = 5x ( 1 - 7x)
D = (x+1)(x+1) +1
D = (x+1)(x+1+2) = (x+1)(x+3)
3/ A = 2 x 10² +10^1 +10^-1 +2 x 10^-2
A = 200 + 10 + 0,1 + 0,02
A = 210, 12
Ecriture scientifique : A = 2,1012 x 10²
3/ 21012 x 10^-2
4/210 +12/100