Հանրահաշիվ

125.

ա) (a+1)(a+1) = a^2 + 2a +1
զ)(a-2)(3-a) = -a^2 + 5a — 6

126.

ա) (5m + 7n)(2n+4m)= 20m^2 + 38mn + 14n^2
զ) (-7x — 4y)(-5x + 7y)= 35x^2 — 29xy — 28y^2

127.

ա) (a+1)(a+1)(a+1)=a^3 + 3a^2 + 3a + 1
զ) (a-b-c)(a-1)=a^2 — a ab +b — ac + c