Question

a.x^2-1=0 b.(x-1)^2+x(5-x)=0 c.(x+1)^2+x(3-x)=0

Answer 1

a =>(x-1)(x+1)=0

=>x=1 hoặc x=-1

b: =>x^2-2x+1+5x-x^2=0

=>3x+1=0

=>x=-1/3

c: =>x^2+2x+1+3x-x^2=0

=>5x+1=0

=>x=-1/5

Answer 2

a)x^2-1=0

\(\Rightarrow\)x^2=1

\(\Rightarrow\)x=1hoặc x=-1

b)x^2-1+5x-1=0

\(\Rightarrow\)x^2-x^2+5x-1=0

\(\Rightarrow\)5x-1=0

\(\Rightarrow\)5x=1 x=1/5

c)x^2+1+3x-x^2=0

\(\Rightarrow\)x^2-x^2+3x+1=0

\(\Rightarrow\)3x=-1

\(\Rightarrow\)x=-1/3