展开 (32x^2-35x=49)(4x-8)

解答

展开

(32 x^{2} - 35 x = 49) (4 x - 8)

128 x^{3} - 256 x^{2} - 35 x = 392

求解步骤

(32 x^{2} - 35 x = 49) (4 x - 8)

= (32 x^{2} - 35 \cdot 49 = x) (4 x - 8)

使用 FOIL 方法:

(a + b) (c + d) = a c + a d + b c + b d

a = 32 x^{2}, b = - 35 x = 49, c = 4 x, d = - 8

= 32 x^{2} \cdot 4 x + 32 x^{2} (- 8) + (- 35 x = 49) \cdot 4 x + (- 35 x = 49) (- 8)

使用加减运算法则

+ (- a) = - a, (- a) (- b) = ab

32 \cdot 4 x^{2} x - 32 \cdot 8 x^{2} - 35 x = 49 \cdot 4 x + 35 x = 49 \cdot 8

化简

32 \cdot 4 x^{2} x - 32 \cdot 8 x^{2} - 35 x = 49 \cdot 4 x + 35 x = 49 \cdot 8 : 128 x^{3} - 256 x^{2} - 35 x = 392

128 x^{3} - 256 x^{2} - 35 x = 392

e x p an d - 4 ln (x - 2) + 3 (1 - x)

e x p an d \frac{3 ( x + 3 ) ( x + 5 )}{x ^{6}}

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

e x p an d \frac{( - 3 x - 8 ) ( x - 1 )}{9}

e x p an d \frac{( x ^{2} - 9 ) ( x - 2 )}{3 x + 6}