Question

Rezolvati in Z ecuatiille:
a) |x|=7
b)|x|=23

si cele din poza

Answer 1

a)|x|=7
x1=7
x2=-7
S={±7}
b)|x|=23
x1=23
x2=-23
S={±23}
c)|x|=0
x=0
S={0}
d)|5x-3|=2
cazul 1:
5x-3=2
5x=5
x=1

cazul2:
5x-3=-2
5x=1
x=1/5 nu apartine lui Z
S={1}
e)|x|=-4
x apartine ∅
f)|4x|=16
cazul 1:
4x=16
x=4
cazul2:
4x=-16
x=-4
S={±4}
k)|x+5|=7
cazul 1:
x+5=7
x=2
cazul 2:
x+5=-7
x=-12
S={-12;2}

Answer 2

a)7, -7
b)23,-23
c)0
d)1
e)x apartine multimii (O taiat, nu am acest semn aici)
f)x apartine multimii O taiat
k)-12, 2
eu am dat direct valorile