Question

[(a-1)×(a-1)×4]÷[(a-4)×(a-4)-1] pentru a =6

Answer 1

[(6-1)×(6-1)×4]:[(6-4)×(6-4)-1] =
[(5×5)×4]:[(2 ×2)-1] =
(25×4):(4-1) =
100:3=33, (3)
Zi-mi care e greseala

Answer 2

$\displaystyle [(a-1) \cdot (a-1) \cdot 4]:[(a-4) \cdot (a-4)-1] \\ \\ a=6 \\ \\ ~[(6-1) \cdot (6-1) \cdot 4]:[(6-4) \cdot (6-4)-1]= \\ \\=(5 \cdot 5 \cdot 4):(2 \cdot 2 -1)=(25 \cdot4):(4-1)=100:3=33,(3)$