Question

determinati multimea A= {x apartine de N*|1,7x-4,5≤14,7}

Answer 1

$1,7\cdot x-4,5 \leq14,7\Rightarrow \frac{17}{10}\cdot x - \frac{45}{10} \leq \frac{147}{10}| \cdot 10 \Rightarrow 17\cdot x - 45 \leq 147 \Rightarrow \\ \\ \Rightarrow 17\cdot x \leq 147+45 \Rightarrow 17\cdot x \leq 192 \Rightarrow x \leq \frac{192}{17} \Rightarrow x \leq 11,2.. \\ \\ \Rightarrow x \in \{1,2,3,4,5,6,7,8,9,10,11\}$