展开 1/4 (2x-7)(2x-1)

解答

展开

\frac{1}{4} (2 x - 7) (2 x - 1)

x^{2} - 4 x + \frac{7}{4}

求解步骤

\frac{1}{4} (2 x - 7) (2 x - 1)

展开

\frac{1}{4} (2 x - 7) (2 x - 1) : \frac{1}{4} (4 x^{2} - 16 x + 7)

= \frac{1}{4} (4 x^{2} - 16 x + 7)

使用分配律:

m (a + b + c) = ma + mb + m c

\frac{1}{4} (4 x^{2} - 16 x + 7) = \frac{1}{4} \cdot 4 x^{2} + \frac{1}{4} (- 16 x) + \frac{1}{4} \cdot 7

= \frac{1}{4} \cdot 4 x^{2} + \frac{1}{4} (- 16 x) + \frac{1}{4} \cdot 7

化简

\frac{1}{4} \cdot 4 x^{2} + \frac{1}{4} (- 16 x) + \frac{1}{4} \cdot 7 : x^{2} - 4 x + \frac{7}{4}

= x^{2} - 4 x + \frac{7}{4}

e x p an d \frac{3 ( 2 x - 3 y )}{( 2 x + 3 y )}

e x p an d 1 - 2 (x + h) - 1 - 2 x

e x p an d \frac{( s - 3 )}{( s + 3 ) ^{2}}

e x p an d \frac{( s + 1 )}{[ ( s + 3 ) ( s + 5 ) ]}

e x p an d (5 - 3)^{2}