(\partial)/(\partial x)((-2x)/(x^2+y^2+1))

解

\frac{\partial}{\partial x} (\frac{- 2 x}{x ^{2} + y ^{2} + 1})

- \frac{2 ( - x ^{2} + y ^{2} + 1 )}{( x ^{2} + y ^{2} + 1 ) ^{2}}

解答ステップ

\frac{\partial}{\partial x} (\frac{- 2 x}{x ^{2} + y ^{2} + 1})

簡素化

\frac{- 2 x}{x ^{2} + y ^{2} + 1} : - \frac{2 x}{x ^{2} + y ^{2} + 1}

= \frac{\partial}{\partial x} (- \frac{2 x}{x ^{2} + y ^{2} + 1})

y

を定数として扱う

定数を除去:

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

= - 2 \frac{\partial}{\partial x} (\frac{x}{x ^{2} + y ^{2} + 1})

商の法則を適用:

(\frac{f}{g})^{'} = \frac{f ^{'} \cdot g - g ^{'} \cdot f}{g ^{2}}

= - 2 \cdot \frac{\frac{\partial}{\partial x} ( x ) ( x ^{2} + y ^{2} + 1 ) - \frac{\partial}{\partial x} ( x ^{2} + y ^{2} + 1 ) x}{( x ^{2} + y ^{2} + 1 ) ^{2}}

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

\frac{\partial}{\partial x} (x^{2} + y^{2} + 1) = 2 x

= - 2 \cdot \frac{1 \cdot ( x ^{2} + y ^{2} + 1 ) - 2 xx}{( x ^{2} + y ^{2} + 1 ) ^{2}}

簡素化

- 2 \cdot \frac{1 \cdot ( x ^{2} + y ^{2} + 1 ) - 2 xx}{( x ^{2} + y ^{2} + 1 ) ^{2}} : - \frac{2 ( - x ^{2} + y ^{2} + 1 )}{( x ^{2} + y ^{2} + 1 ) ^{2}}

= - \frac{2 ( - x ^{2} + y ^{2} + 1 )}{( x ^{2} + y ^{2} + 1 ) ^{2}}