展开 p(x,y)A(-3,-4)B(1,2)

解答

展开

p (x, y) A (- 3, - 4) B (1, 2)

- 3 (1 \cdot 2,) p A B (, x y), - 4 (1 \cdot 2,) p A B (, x y)

求解步骤

p (x, y) A (- 3, - 4) B (1, 2)

= (- 3, - 4) (1 \cdot 2,) p A B (, x y)

使用分配律:

a (b - c) = ab - a c

a = p (x, y) A B (1, 2), b = - 3,, c = 4

= p (x, y) A B (1, 2) (- 3,) - p (x, y) A B (1, 2) \cdot 4

使用加减运算法则

+ (- a) = - a

= - 3 (1 \cdot 2,) p A B (, x y), - 4 (1 \cdot 2,) p A B (, x y)

\frac{d}{d x} ((z) (\frac{y}{x + y} - z))

e x p an d \frac{r ( 9 - 2 r )}{( r ^{2} - 9 r - 9 )}

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

e x p an d (x - \frac{1}{e ^{2}})^{2}

e x p an d \frac{3 x ( a - x ) ^{4}}{4}