\(63x^2-16x+1=0\)
\(\Leftrightarrow63x^2-9x-7x+1=0\)
\(\Leftrightarrow9x\left(7x-1\right)-\left(7x-1\right)=0\)
\(\Leftrightarrow\left(9x-1\right)\left(7x-1\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}9x-1=0\\7x-1=0\end{cases}\Leftrightarrow\orbr{\begin{cases}x=\frac{1}{9}\\x=\frac{1}{7}\end{cases}}}\)
Bài làm:
Ta có: \(63x^2-16x+1=0\)
\(\Leftrightarrow\left(63x^2-9x\right)-\left(7x-1\right)=0\)
\(\Leftrightarrow9x\left(7x-1\right)-\left(7x-1\right)=0\)
\(\Leftrightarrow\left(7x-1\right)\left(9x-1\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}7x-1=0\\9x-1=0\end{cases}}\Rightarrow\orbr{\begin{cases}x=\frac{1}{9}\\x=\frac{1}{7}\end{cases}}\)
63x2 - 16x + 1 = 0
<=> 63x2 - 9x - 7x + 1 = 0
<=> 9x( 7x - 1 ) - 1( 7x - 1 ) = 0
<=> ( 7x - 1 )( 9x - 1 ) = 0
<=> \(\orbr{\begin{cases}7x-1=0\\9x-1=0\end{cases}\Leftrightarrow}\orbr{\begin{cases}x=\frac{1}{7}\\x=\frac{1}{9}\end{cases}}\)
Bài làm :
Ta có :
\(63x^2-16x+1=0\)
\(\Leftrightarrow\left(63x^2-9x\right)-\left(7x-1\right)=0\)
\(\Leftrightarrow9x\left(7x-1\right)-\left(7x-1\right)=0\)
\(\Leftrightarrow\left(7x-1\right)\left(9x-1\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}7x-1=0\\9x-1=0\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}7x=1\\9x=1\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=\frac{1}{7}\\x=\frac{1}{9}\end{cases}}\)
Chúc bạn học tốt !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Tìm x:
63x2 - 16x + 1 = 0
<=> 63x2 - 9x - 7x + 1 = 0
<=> 9x( 7x - 1 ) - 1( 7x - 1 ) = 0
<=> ( 7x - 1 )( 9x - 1 ) = 0
\(\orbr{\begin{cases}7x-1=0\\9x-1=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=\frac{1}{7}\\x=\frac{1}{9}\end{cases}}\)