Question

Tentukan himpunan penyelesaian dari :
a. 4 < |x+2| + |x-1| < 5
b. |x-2| ≤ |x+1|

mohon bantuannya ya! ^_^

Answer 1

B. |x-2| ≤ |x+1|
|f(x)| ≤ |g(x)|
=> (f(x) + g(x)).(f(x)- g(x)) ≤ 0
=> (x-2+x+1)(x-2-x-1) ≤ 0
=> (2x -1)(-3) ≤ 0
=> -6x + 3 ≤ 0
=> -6x ≤ -3
=> x ≤ -3/-6
=> x ≤ 1/2
HP = {x|x ≤ 1/2}
yg a aku gak tau