展开 (x+dx)(ycos(x))

解答

展开

(x + d x) (y cos (x))

x y cos (x) + y cos (x) d x

求解步骤

(x + d x) (y cos (x))

使用分配律:

a (b + c) = ab + a c

a = (y cos (x)), b = x, c = d x

= (y cos (x)) x + (y cos (x)) d x

= x (y cos (x)) + (y cos (x)) d x

去除括号:

(a) = a

= x y cos (x) + y cos (x) d x

e x p an d 3.3 (3 - 0.2 h) h^{1, 5}

e x p an d \frac{( θ - X _{2} θ ^{3} ) ^{2}}{2}

e x p an d (- y^{2} + 1) d x

e x p an d (x^{2} + x - 2)^{5}

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