bjr
ex 1
(1+4x) (x-2) = (x-2)²
(1+4x) (x-2) - (x-2)² = 0
(x-2) (1+4x - (x-2)) = 0
(x-2) (1+4x-x+2) = 0
(x-2) (3x+3) = 0
3 (x-2)(x+1) = 0
(1+x) / (3-x)
1+x >0 qd x > -1
3-x > 0 qd x < 3
x -∞ -1 3 +∞
1+x - + +
3-x + + !! -
quotient - + !! -
tu conclus
4 / (3-x) ≤ 1
4 ≤ 3-x
4 - 3 + x ≤ 0
x ≤ -1