展开 (6x+3y=1,2)(3x+y=5)

解答

展开

(6 x + 3 y = 1, 2) (3 x + y = 5)

18 x^{2} + 6 x y = 5

求解步骤

(6 x + 3 y = 1, 2) (3 x + y = 5)

= (6 x + 3 \cdot 1 \cdot 2 =, y) (3 x + 5 = y)

使用 FOIL 方法:

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

a = 6 x, b = 3 y = 1, 2, c = 3 x, d = y = 5

6 x \cdot 3 x + 6 x y = 5 + 3 y = 1, 2 \cdot 3 x + 3 y = 1, 2 y = 5

6 \cdot 3 xx + 6 x y = 5 + 3 y = 1, 2 \cdot 3 x + 3 y = 1, 2 y = 5

乘开

6 \cdot 3 xx + 6 x y : 18 x^{2} + 6 x y

18 x^{2} + 6 x y = 5

e x p an d (- 1)^{x + 1} (\frac{π ^{3}}{x} - \frac{6 π}{x ^{3}})

e x p an d P (1, 4, 6) Q (- 2, 5, - 1) R (1, - 1, 1)

s im pl i f y x (\frac{x}{2} - \frac{1}{4})

e x p an d (y + \frac{1}{y ^{2}})^{6}

s im pl i f y (x - 4) \times (x + 2)