derivative of (sqrt(x)-7/(sqrt(x)+5))

解

\frac{d}{d x} (\frac{x - 7}{x + 5})

\frac{6}{x ( x + 5 ) ^{2}}

解答ステップ

\frac{d}{d x} (\frac{x - 7}{x + 5})

商の法則を適用:

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

= \frac{\frac{d}{d x} ( x - 7 ) ( x + 5 ) - \frac{d}{d x} ( x + 5 ) ( x - 7 )}{( x + 5 ) ^{2}}

\frac{d}{d x} (x - 7) = \frac{1}{2 x}

\frac{d}{d x} (x + 5) = \frac{1}{2 x}

= \frac{\frac{1}{2 x} ( x + 5 ) - \frac{1}{2 x} ( x - 7 )}{( x + 5 ) ^{2}}

簡素化

\frac{\frac{1}{2 x} ( x + 5 ) - \frac{1}{2 x} ( x - 7 )}{( x + 5 ) ^{2}} : \frac{6}{x ( x + 5 ) ^{2}}

= \frac{6}{x ( x + 5 ) ^{2}}