Question

4. Fie x natural. Rezolvați inecuațiile:
a) 5.x < 30;
b) 7 x+5 ≤ 61;
c) 204-3x > 192.

Sa fie cu inecuații!Multumesc!

Answer 1

Explicație pas cu pas:

a)

$5\cdot x < 30\\x < \frac{30}{5} \\x < 6 \\x \in \mathbb{N} \implies x \in \{0,1,2,3,4,5\}$

b)

$7\cdot x +5 \leq 61\\7x\leq 61-5\\7x\leq 56\\x\leq \frac{56}{7} \\x\leq 8\\ \ x \in \mathbb{N} \implies x \in \{0,1,2,3,4,5,6,7,8\}$

c)

$204-3x > 192\\204-192 > 3x\\12 > 3x\\4 > x \ \iff \ x < 4\\x \in \mathbb{N} \implies x \in \{0,1,2,3\}$