Question

Спрости вирази:

(a + 2b)(3a – 4b) + 3ab – 3a2

–7mn + (m + 5n)(2m – 3n)

Answer 1

Ответ:

1. (a + 2b)(3a – 4b) + 3ab – 3a^2 = 3a^2 - 4ab + 6ab - 8b^2 + 3ab - 3a^2 = -8b^2 + 9ab.

2. -7mn + (m + 5n)(2m – 3n) = -7mn + 2m^2 - 3mn + 10mn - 15n^2 = 2m^2 + mn - 15n^2