Question

Biến đa thức thành nhân tử:

A.) x²+7x+12

B.) x²+2x-8

C.) x²+11x+30

Answer 1

a) x²+7x+12=x²+4x+3x+12=x(x+4)+3(x+4)=(x+3)(x+4)

Answer 2

a) x^2 + 7x + 12

= x^2 + 3x + 4x + 12

= x (x + 3) + 4 (x + 3)

= (x + 3)(x + 4)

b) x^2 + 2x - 8

= x^2 - 2x + 4x - 8

= x (x - 2) + 4 (x - 2)

= (x - 2)(x + 4)

c) x^2 + 11x + 30

= x^2 + 5x + 6x + 30

= x (x + 5) + 6 (x + 5)

= (x + 5)(x + 6)

Answer 3

b) x²+2x-8=x²+2x+1-1-8=(x²+2x+1)-9=(x+1)²-3²

=(x+1-3)(x+1+3)=(x-2)(x+4)