Question

Bài 1: Phân tích đa thức thành nhân tử:

A. x² - 6 

B. a² - b² + a + b 

C. ( a + 9 )² - 36a² 

 

 

 

Answer 1

\(a^2-b^2+a+b=\left(a-b\right)\left(a+b\right)+a+b=\left(a-b+1\right)\left(a+b\right)\)

Answer 2

\(c,\left(a+9\right)^2-36a^2=\left(a+9\right)^2-\left(6a\right)^2\)

\(=\left(a+9-6a\right)\left(a+9+6a\right)\)

Answer 3

a/ x² - 6 = ( x + \(\sqrt{6}\)) ( x - \(\sqrt{6}\))

b/ ...

c/ ( a + 9 )² - 36a² = ( a + 9 )² - 6a²

= ( a + 9 + 6a ) ( a + 9 - 6a )

= ( 7a + 9 ) ( -5a + 9 )

Answer 4

\(x^2-6=x^2-\left(\sqrt{6}\right)^2=\left(x-\sqrt{6}\right)\left(x+\sqrt{6}\right)\)

\(a^2-b^2+a+b=\left(a-b\right)\left(a+b\right)+\left(a+b\right)=\left(a+b\right)\left(a-b+1\right)\)

\(\left(a+9\right)^2-36a^2=\left(a+9\right)^2-\left(6a\right)^2=\left(a+9-6a\right)\left(a+9+6a\right)=\left(9-5a\right)\left(7a+9\right)\)

Answer 5

a) \(x^2-6=x^2-\left(\sqrt{6}\right)^2=\left(x+\sqrt{6}\right)\left(x-\sqrt{6}\right)\)

b) \(\left(a^2-b^2\right)+\left(a+b\right)=\left(a+b\right)\left(a-b\right)+\left(a+b\right)\)

\(=\left(a+b\right)\left(a-b+1\right)\)

Answer 6

a) \(x^2-6=x^2-\left(\sqrt{6}\right)^2=\left(x+\sqrt{6}\right)\left(x-\sqrt{6}\right)\)

b) \(a^2-b^2+a+b=\left(a+b\right)\left(a-b\right)+\left(a+b\right)=\left(a+b\right)\left(a-b+1\right)\)

c) \(\left(a+9\right)^2-36a^2=\left(a+9\right)^2-\left(6a\right)^2=\left(a+9-6a\right)\left(a+9+6a\right)=\left(9-5a\right)\left(7a+9\right)\)