$\text{Đáp án + giải thích các bước giải}$
$\text{a) $\dfrac{64x^{3} + 1 }{16x^{2} - 1}$}$ $\text{=$\dfrac{A}{4x - 1}$}$
$\text{⇒ A. ( 16x² - 1 ) = ( 64x³ + 1 ) ( 4x - 1 )}$
$\text{⇒ A ( 4x - 1 ) ( 4x + 1 ) = ( 4x + 1 ) ( 16x² - 4x + 1 ) ( 4x - 1 ) }$
$\text{⇒ A ( 16x² - 1 ) = ( 16x² - 1 ) ( 16x² - 4x + 1 )}$
$\text{⇔ A = $\dfrac{( 16x² - 1 ) ( 16x² - 4x + 1 )}{16x^{2} - 1}$}$
$\text{⇔ A = 16x² - 4x + 1}$
$\text{b) $\dfrac{2x - y - 1}{4x - 2y}$ }$ $\text{= $\dfrac{4x^{2} - 2x - y^{2} - y}{B}$}$
$\text{⇒ D(2x-y-1)=(4x-2y)(4x²-2x-y²-y)}$
$\text{⇒ D ( 2x - y - 1 ) = ( 4x - 2y ) ( 4x² - y² - 2x - y )}$
$\text{⇒ D ( 2x - y - 1 ) = ( 4x - 2y ) [ ( 2x - y ) ( 2x + y ) - ( 2x + y ) ]}$
$\text{⇒ D ( 2x - y - 1 ) = ( 4x - 2y ) ( 2x + y ) ( 2x - y - 1 ) }$
$\text{⇔ D = $\dfrac{( 4x - 2y ) ( 2x + y ) ( 2x - y - 1 )}{2x - y - 1}$ }$
$\text{⇔ D = ( 4x - 2y ) ( 2x + y )}$
$\text{⇔ D = 8x² - 4y²}$
$\text{Cho mình xin câu tl hay nhất nha}$
