展开 (15-x)^3

解答

展开

(15 - x)^{3}

3375 - 675 x + 45 x^{2} - x^{3}

求解步骤

(15 - x)^{3}

使用完全立方公式:

(a - b)^{3} = a^{3} - 3 a^{2} b + 3 a b^{2} - b^{3}

(15 - x)^{3} = 1 5^{3} - 3 \cdot 1 5^{2} x + 3 \cdot 15 x^{2} - x^{3}

= 1 5^{3} - 3 \cdot 1 5^{2} x + 3 \cdot 15 x^{2} - x^{3}

化简

1 5^{3} - 3 \cdot 1 5^{2} x + 3 \cdot 15 x^{2} - x^{3} : 3375 - 675 x + 45 x^{2} - x^{3}

= 3375 - 675 x + 45 x^{2} - x^{3}

f a c t or 2 b \cdot a + b

e x p an d 108 a - 3 (b - c)^{2}

s im pl i f y 2 x (5 + 3 x) - 4 (x + 5)

s im pl i f y \frac{1}{( j ^{2} w ^{2} c )}

s im pl i f y x^{2} - \frac{x ^{4}}{4} + \frac{x ^{6}}{24}