Salut.
Cunoaștem formula:
[tex]\boxed{(a-b)^{2}=a^{2}-2ab+b^{2}}[/tex]
Prin urmare:
[tex]\displaystyle{ (1- 5x)^{2}=1^{2}-2 \cdot 1\cdot 5x + (5x)^{2} }[/tex]
[tex]\displaystyle{ =1 -2 \cdot 5x + 25 \cdot x^{2} }[/tex]
[tex]\displaystyle{ =25x^{2}-10x+1 }[/tex]
Răspuns:
Varianta D
- Lumberjack25