1) a= (50×51)/2 - 25 ×2=
a= 25×51−25×2= 25×(51-2)=
a= 25×49 = 5² × 7²
√a= 5 ×7 = 35
2)= 120×121/2 + 4×121 =
a= 60 ×121 + 4 ×121 = 121×( 60+4)=
a= 121 × 64 = 11² × 8²
√α= 11×8 =88
3)a= 60×( 4+60 ) + 64×(64 - 43)
a= 60×64 + 64× 21 = 64×( 60 +21) =
a= 64 x 81 = 8²× 9²=
√a = 8×9= 72
4) a= 101²− 2×99×101+99²=
a= (101+99)² = 200²
√a=200
sper ca te.am ajutat si sper ca e corect !!
