Bài 3 : Hằng đẳng thức dạng ( A – B ) ( A + B ) = A^2 – B^2
a) -( 5 + 4y ) ( 5 – 4y )
b) ( 2x – 3 ) ( 2x + 3 )
c) (1/2 x – 2y ) ( 1/2 x + 2y )
Bài 3 : Hằng đẳng thức dạng ( A – B ) ( A + B ) = A^2 – B^2 a) -( 5 + 4y ) ( 5 – 4y ) b) ( 2x – 3 ) ( 2x + 3 ) c) (1/2 x – 2y ) ( 1/2 x + 2y )
By Rylee
`a,-(5+4y)(5-4y)=-(25-16y^2)=-25+16y^2`
`b,(2x-3)(2x+3)=4x^2-9`
`c,(1/2x-2y)(1/2x+2y)=1/4x^2-4y^2`
a) $-(5+4y)(5-4y)=-(25-16y^2)=16y^2-25$
b) $(2x-3)(2x+3)=4x^2-9$
c) `(1/2 x-2y)(1/2 x+2y)=1/4 x^2-4y^2`