👤

A=2021+2×(1+2+3+…+2020)
Este patrat perfect ?


Cu rezolvare va rog urgent!!!


Răspuns :

A=2021+2*2020*2021:2
A=2021+2020*2021
A=2021(1+2020)
A=2021*2021
A=2021²
A=2021+2×(1+2+3+…+2020) =
=
2021+2×2020 ×2021/2=
 
=2021+2020 ×2021=
=2021 ×(1+2020)=
=2021 ×2021=2021² deci patrat perfect