Question

Tìm x, biết:

a) 2x(x-2016) - x+2016=0

b)(x+2)²-(x-2)(x+2)=0

Answer 1

a, (x-2016)(2x-1)=0

<=>x=2016 hoặc x=-1/2

b, (x+2)(x+2-x+2)=0

<=>4(x+2)=0

<=>x+2=0

<=>x=-2

Answer 2

a) 2x(x-2016)-x+2016=0

=>2x(x-2016)-(x-2016)=0

=>(x-2016)(2x-1)=0

=>\(\left\{{}\begin{matrix}x-2016=0\\2x-1=0\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=2016\\x=\dfrac{1}{2}\end{matrix}\right.\)

vậy x=2016 hoặc x=\(\dfrac{1}{2}\)

b) (x+2)²-(x-2)(x+2)=0

=>(x+2)[(x+2)-(x-2)]=0

=>(x+2)(x+2-x+2)=0

=>(x+2)4=0

=>x+2=0

=>x=-2

vậy x=-2