(\partial)/(\partial x)(cos(3x+6y))

解

\frac{\partial}{\partial x} (cos (3 x + 6 y))

- sin (3 x + 6 y) \cdot 3

解答ステップ

\frac{\partial}{\partial x} (cos (3 x + 6 y))

y

を定数として扱う

連鎖法則を適用:

- sin (3 x + 6 y) \frac{\partial}{\partial x} (3 x + 6 y)

= - sin (3 x + 6 y) \frac{\partial}{\partial x} (3 x + 6 y)

\frac{\partial}{\partial x} (3 x + 6 y) = 3

= - sin (3 x + 6 y) \cdot 3