Question

Determinați, în fiecare caz, nr. naturale x, știind că:
b)x+3<11, x<11-3
c)x-7<13
d)x-3<6
e)4+x ≤ 10
f)2+x ≤ 12
g) x+17>23
h)x+21 ≥ 43
i)4•x<24
j)3•x ≤ 33
k)x:2<7
l)x:4 ≤ 2
m)x:3<5
n)x:6 ≤ 4
o)3•x+11<44
p)3+7•x ≤ 52
r)5•x-23 ≥ 22
s)6•x-18 ≥ 72
t)3 la puterea x ≤ 81
u)10 la puterea x< 100.000
v)2 la puterea 2•x+1 ≥128
x)4 la puterea 3•x-5>256


Ma poate ajuta cineva, va rog?..
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Answer 1

Ti-am facut toata tema in jumatate de ora :)

b)x+3<11, x<11-3

x<8

x={0, 1, 2, 3, 4, 5, 6, 7}

c)x-7<13

x<20

x={0, 1, 2, ... 19}

d)x-3<6

x<9

x={0, 1, 2, ... 8}

e)4+x ≤ 10

x<= 6

x={0, 1, 2, ... 6}

f)2+x ≤ 12

x<=10

x={0, 1, 2, ... 10}

g) x+17>23

x>6

x={7, 8, ... +inf}

h)x+21 ≥ 43

x>=22

x={22, 23, ... +inf}

i)4•x<24

x<6

x={0, 1, 2, ... 5}

j)3•x ≤ 33

x<=11

x={0, 1, 2, ... 11}

k)x:2<7

x<14

x={0, 2, 4, .. 12}

l)x:4 ≤ 2

x<=8

x={0, 4, 8}

m)x:3<5

x<15

x={0, 3, 5, 15}

n)x:6 ≤ 4

x<=24

x={0, 6, 12, 18, 24}

o)3•x+11<44

3*x<33

x<11

x={0, 1, 2, ... 10}

p)3+7•x ≤ 52

7*x<=49

x<=7

x={0, 1, 2, ... 7}

r)5•x-23 ≥ 22

5*x>=45

x>=9

x={0, 1, 2, ... 9}

s)6•x-18 ≥ 72

6*x>=90

x>=15

x={15, 16, ... +inf}

t)3 la puterea x ≤ 81

3^x <= 3^4

x<=4

x={0, 1, 2, 3, 4}

u)10 la puterea x< 100.000

10^x < 10^5

x<5

x={0, 1, 2, 3, 4}

v)2 la puterea 2•x+1 ≥128

2^(2*x+1)>2^(7)

2*x+1 > 7

2*x > 6

x>3

x={4, 5, +inf}

x)4 la puterea 3•x-5>256

4^(3*x-5) > 4^4

3*x-5 > 4

3*x > 9

x>3

x={4, 5, ... +inf}