Question

Rezolvati in R ecuatia:
a) |3x-7|=8
d) |2x(x-0.5)|=3

Answer 1

d) 2x(x-0,5)≥0
   2x(x-0,5)=3
 
  2x(x-0,5)<0
  2x(x-0,5)=3

2x²-x=3⇔2x²-x-3=0
Δ=b²-4ac=1-4×2×(-3)=25


a) |3x-7|=8⇒3x-7=8 sau 3x-7=-8
⇒3x=15 sau 3x=-1
⇒x=5 sau x=
⇒S={, 5}