展开 (f(x)=2,x+5)*(g(x)=x+5)

解答

展开

(f (x) = 2, x + 5) \cdot (g (x) = x + 5)

f (x) = x + 25

求解步骤

(f (x) = 2, x + 5) (g (x) = x + 5)

= (2 =, x f (x) + 5) (= xg (x) + 5)

使用 FOIL 方法:

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

a = f (x) = 2, x, b = 5, c = g (x) = x, d = 5

f (x) = 2, xg (x) = x + f (x) = 2, x \cdot 5 + 5 g (x) = x + 5 \cdot 5

f (x) = 2, xg (x) = x + f (x) = 2, 5 x + 5 g (x) = x + 5 \cdot 5

乘开

x + 5 \cdot 5 : x + 25

f (x) = x + 25

e x p an d - 3 (3 x - 5 = 7 - 4 x)

e x p an d (4 + 6 x) x^{3} e^{6 x}

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

s im pl i f y (x - 14)^{2}

\frac{\partial}{\partial t} ((z) (x^{2} y + x y^{2}))