展开 (x+y=10,)(x-y=6)

解答

展开

(x + y = 10,) (x - y = 6)

x^{2} - x y = 6

求解步骤

(x + y = 10,) (x - y = 6)

= (x + 10 =, y) (x - 6 = y)

使用 FOIL 方法:

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

a = x, b = y = 10,, c = x, d = - y = 6

xx + x (- y = 6) + y = 10, x + y = 10, (- y = 6)

使用加减运算法则

+ (- a) = - a

xx - x y = 6 + y = 10, x - y = 10, y = 6

乘开

xx - x y : x^{2} - x y

x^{2} - x y = 6

e x p an d 6 (2 x - 25 = - 18)

e x p an d (e^{y} + 1)^{3}

e x p an d - \frac{16 ( x + 6 )}{9 ( y - 8 )}

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

e x p an d \frac{x ^{2} ( x - 3 )}{5 x ^{2} - 1}