Question

Phân tích đa thức thành nhân tử:

a) \(a^2-9\)

b) \(9a^2-1\)

c) \(36x^{^{ }2}-49y^2\)

d) \(\dfrac{1}{4}a^2-5^2\)

Answer 1

a) a² - 9 = ( a-3 ) ( a+3 )

b) 9a² - 1 = ( 3a -1) ( 3a+1 )

c) 36x² - 49y² = ( 6x -7y)( 6x+7y)

d) \(\dfrac{1}{4}\)a² - 5² = ( \(\dfrac{1}{2}\)a -5) ( \(\dfrac{1}{2}\)a+5)

Answer 2

a) \(a^2-9=\left(a-3\right)\left(a+3\right)\)

b) \(9a^2-1=\left(3a-1\right)\left(3a+1\right)\)

c) \(36x^2-49y^2=\left(6x-7y\right)\left(6x+7y\right)\)

d) \(\dfrac{1}{4}a^2-5^2=\left(\dfrac{1}{2}a-5\right)\left(\dfrac{1}{2}a+5\right)\)