Question

1 вариант
Упростите выражение:
(а - в) (c - d)
(x + 3) (x - 2)
(3y - 1) (5y + 7)
(4a 3 – 3b2) (2b2 – 2a2)
(3y - 4) (9y2 – 2y + 4y3)

Answer 1

$(a - b) (c - d)=ac-bc-ad+bd\\\\(x+ 3) (x - 2)=x^2+3x-2x-6=x^2+x-6\\\\(3y - 1) (5y + 7)=15y^2-5y+21y-7=15y^2+16y-7\\\\(4a^3 -3b^2) (2b^2 -2a^2)=8a^3b^2-6b^4-8a^5+6a^2b^2\\\\(3y - 4) (9y^2 - 2y + 4y^3)=27y^3-36y^2-6y^2+8y+12y^4-16y^3=\\\\=11y^3-42y^2+8y+12y^4$