展开-4x^2(xy^2+3x^-4)

解答

展开

- 4 x^{2} (x y^{2} + 3 x^{-} 4)

- 4 x^{3} y^{2} - 48 x^{2}

求解步骤

- 4 x^{2} (x y^{2} + 3 x^{-} \cdot 4)

= - 4 x^{2} (x y^{2} + 3 \cdot 4 x^{-})

使用分配律:

a (b + c) = ab + a c

a = - 4 x^{2}, b = x y^{2}, c = 3 x^{-} \cdot 4

= - 4 x^{2} x y^{2} + (- 4 x^{2}) \cdot 3 x^{-} \cdot 4

使用加减运算法则

+ (- a) = - a

= - 4 x^{2} x y^{2} - 4 \cdot 3 \cdot 4 x^{2} x^{-}

化简

- 4 x^{2} x y^{2} - 4 \cdot 3 \cdot 4 x^{2} x^{-} : - 4 x^{3} y^{2} - 48 x^{2}

= - 4 x^{3} y^{2} - 48 x^{2}

e x p an d (1, 1, 4) (x^{2}, x, - 3)

e x p an d e x^{2} \cdot (4 x^{2} + 3 cos (y))

e x p an d \frac{10}{( s + 4 ) ( s + 2 ) ^{2}}

e x p an d - \frac{1}{y ( y - 1 )}

e x p an d \frac{1}{2 ( 10 - 6 y )}