Bonjour,
a. (4x − 1)² – (x+6)²
16x² -8x +1 -( x² +12x +36) =
16x² -8x +1 - x² -12x -36 =
15x² 620x -35
b. (3x + 7)² – 4(x+1)
9x² +42x +49 -4x -4=
9x² +38x +45
c. 6(5x – 2)(5x + 2)-3(x+6)
(30x -12)(5x+2) -3x -18=
150x² +60x - 60x -24 -3x -18=
150x² -3x -42
d. (2x+3)(3x – 4)
6x² -8x +9x -12=
6x² +x -12
e.(4x+3)(4x – 3)+(4x +3)
16x² -12x +12x -9 +4x +3=
16x² +4x -6
f.(4x - 5)(3x - 7)
12x² -28x -15x+35=
12x² -43x +35
