Question

Giải phương trình 

2x^2-6x+1=0

4x^2-12x+5=0

2x^2+5x+3=0

x^2+x-2=0

Cảm ơn!

Answer 1

           \(4x^2-12x+5=0\)

\(\Leftrightarrow\)\(4x^2-10x-2x+5=0\)

\(\Leftrightarrow\)\(2x\left(2x-5\right)-\left(2x-5\right)=0\)

\(\Leftrightarrow\)\(\left(2x-1\right)\left(2x-5\right)=0\)

\(\Leftrightarrow\)\(\orbr{\begin{cases}2x-1=0\\2x-5=0\end{cases}}\)\(\Leftrightarrow\)\(\orbr{\begin{cases}x=0,5\\x=2,5\end{cases}}\)

Vậy...

Answer 2

\(I\)\(don't\)\(know\)\(it\)!!!!!!!!!!!!!!!!