Question

Va rog ajutati-ma, am uitat cum se rezolva acest tip de exercitiu! Ofer 24 de puncte

Answer 1

$a)~19+x \leq 43 \\ x \leq 43-19 \\ x \leq 24 ,~x \in N \Rightarrow x \in \{ 0,1,2,3,...,24 \}. \\ \\ b)~28-x \geq 11 \\ 28-11 \geq x \\ 17 \geq x ,~x \in N \Rightarrow x \in \{0,1,2,3,...,17\}. \\ \\ c)~x+38-18\ \textless \ 83 \\ x\ \textless \ 83-38+18 \\ x\ \textless \ 63,~ x \in N \Rightarrow x \in \{0,1,2,3,...,62 \}. \\ \\ d)~41+x-39\ \textless \ 83-77 \\ x\ \textless \ 83-77-41+39 \\ x\ \textless \ 4 , ~x \in N \Rightarrow x \in \{0,1,2,3 \}.$

Retine! Multimea in care se cere sa se rezolve ecuatia (inecuatia in cazul acesta) nu este neglijabila, deoarece exista diverse tipuri de probleme pentru fiecare multime in parte!

Answer 2

a. 19+x≤43
⇒x≤24⇒x=[0,1,2,...,24];
b. 28-x≥11
⇒x≤17⇒x=[0,1,2,...,17];
c. x+20<83
⇒x<63⇒x=[0,1,2,...,62];
d. 41+x-39<6
⇒2+x<6⇒x<4⇒x=[0,1,2,3];