d/(da)(sin(a)+sin(2a)+sin(3a))

解答

\frac{d}{d a} (sin (a) + sin (2 a) + sin (3 a))

cos (a) + cos (2 a) \cdot 2 + cos (3 a) \cdot 3

求解步骤

\frac{d}{d a} (sin (a) + sin (2 a) + sin (3 a))

使用微分加减法定则:

(f \pm g)^{'} = f^{'} \pm g^{'}

= \frac{d}{d a} (sin (a)) + \frac{d}{d a} (sin (2 a)) + \frac{d}{d a} (sin (3 a))

\frac{d}{d a} (sin (a)) = cos (a)

\frac{d}{d a} (sin (2 a)) = cos (2 a) \cdot 2

\frac{d}{d a} (sin (3 a)) = cos (3 a) \cdot 3

= cos (a) + cos (2 a) \cdot 2 + cos (3 a) \cdot 3

in v erse l a pl a ce - \frac{5 s}{( s ^{2} + 1 ) ^{2}}

\int (x + 1) (x + 3) d x

in v erse l a pl a ce \frac{- 0.1 s}{s ^{2} - 9.8}

d er i v a t i v e y = \frac{4}{3} (x + 1)^{\frac{3}{2}}

\int_{0}^{- 0.5} 150 x d x