Question

Phân tích đa thức thành nhân tử:  A = x⁴+5x³-7x²-41x-30

Answer 1

= x^4  + x^3  + 4x^3 + 4x^2 - 11x^2  - 11x -30x - 3 

= x^3 ( x + 1) + 4x^2 ( x + 1)- 11x( x + 1) - 30 ( x+ 1)

= ( x + 1)(x^3 + 4x^2 - 11x - 30)

=  ( x + 1) [ x^3 - 3x^2 + 7x^2 - 21x + 10x - 30]

= ( x  + 1) [ x^2 ( x - 3) + 7x(x - 3) + 10 ( x- 3) ] 

= ( x + 1 ) (x - 3 )(x^2 + 7x + 10)

= ( x + 1)(x - 3) [ x^2 + 2x + 5x + 10)

= ( x+ 1)(x-3) [ x(x+2) + 5(x+2) ] 

=(x + 1)(x-3)(x+2)(x+5)

 

Answer 2

khong co bai nao la kho chi la ko biet lam

Answer 3

= x⁴ + x³ + 4x³ + 4x² - 11x² - 11x - 30x - 30

= x³. (x + 1) + 4x².(x+1) -11x.(x+1) - 30.(x+1)

= (x+1).(x³ + 4x² -11x - 30) = (x+1).(x³ - 3x² + 7x² - 21x + 10x - 30)

= (x+1).[x².(x - 3) + 7x.(x - 3) + 10.(x - 3)] = (x +1).[(x - 3).(x² + 7x + 10)] = (x+1).(x - 3). (x² + 2x + 5x + 10) 

= (x + 1).(x - 3).(x + 2).(x + 5) 

Answer 4

Chỉ cho mik cách đề tìm thừa số chung (x+1) đi, mik bấm máy casio mà ko ra. Thanks