A) .(x+3).(2x^2+x-2) B) (x+3).(x^2-4x+9) C) .(7x-1).(2x^2-5x+3)
^ là mũ nha mn
A) .(x+3).(2x^2+x-2) B) (x+3).(x^2-4x+9) C) .(7x-1).(2x^2-5x+3) ^ là mũ nha mn
By Hailey
By Hailey
A) .(x+3).(2x^2+x-2) B) (x+3).(x^2-4x+9) C) .(7x-1).(2x^2-5x+3)
^ là mũ nha mn
…
Đáp án:
a. $(x + 3)(2x^2 + x – 2) = 2x^3 + x^2 – 2x + 6x^2 + 3x – 6$
$= 2x^3 + 7x^2 + x – 6$
b. $(x + 3)(x^2 – 4x + 9) = x^3 – 4x^2 + 9x + 3x^2 – 12x + 27$
$= x^3 – x^2 – 3x + 27$
c. $(7x – 1)(2x^2 – 5x + 3) = 14x^3 – 35x^2 + 21x – 2x^2 + 5x – 3$
$= 14x^3 – 37x^2 + 26x – 3$