(\partial)/(\partial x)(2xy^3cos(x^2y^3))

解

\frac{\partial}{\partial x} (2 x y^{3} cos (x^{2} y^{3}))

2 y^{3} (cos (x^{2} y^{3}) - 2 x^{2} y^{3} sin (x^{2} y^{3}))

解答ステップ

\frac{\partial}{\partial x} (2 x y^{3} cos (x^{2} y^{3}))

y

を定数として扱う

定数を除去:

(a \cdot f)^{'} = a \cdot f^{'}

= 2 y^{3} \frac{\partial}{\partial x} (x cos (x^{2} y^{3}))

積の法則を適用:

(f \cdot g)^{'} = f^{'} \cdot g + f \cdot g^{'}

f = x, g = cos (x^{2} y^{3})

= 2 y^{3} (\frac{\partial}{\partial x} (x) cos (x^{2} y^{3}) + \frac{\partial}{\partial x} (cos (x^{2} y^{3})) x)

\frac{\partial}{\partial x} (x) = 1

\frac{\partial}{\partial x} (cos (x^{2} y^{3})) = - sin (x^{2} y^{3}) \cdot 2 y^{3} x

= 2 y^{3} (1 \cdot cos (x^{2} y^{3}) + (- sin (x^{2} y^{3}) \cdot 2 y^{3} x) x)

簡素化

2 y^{3} (1 \cdot cos (x^{2} y^{3}) + (- sin (x^{2} y^{3}) \cdot 2 y^{3} x) x) : 2 y^{3} (cos (x^{2} y^{3}) - 2 x^{2} y^{3} sin (x^{2} y^{3}))

= 2 y^{3} (cos (x^{2} y^{3}) - 2 x^{2} y^{3} sin (x^{2} y^{3}))