\( \int {\cos \ln xdx} = \)( )
A: \( {x \over 2}(\cos \ln x + \sin \ln x) + C \)
B: \( {x \over 2}(\cos \ln x - \sin \ln x) + C \)
C: \(- {x \over 2}(\cos \ln x + \sin \ln x) + C \)
D: \(- {x \over 2}(\cos \ln x - \sin \ln x) + C \)
A: \( {x \over 2}(\cos \ln x + \sin \ln x) + C \)
B: \( {x \over 2}(\cos \ln x - \sin \ln x) + C \)
C: \(- {x \over 2}(\cos \ln x + \sin \ln x) + C \)
D: \(- {x \over 2}(\cos \ln x - \sin \ln x) + C \)
举一反三
- $\int {{1 \over {3 + 5\cos x}}} dx = \left( {} \right)$ A: ${1 \over 4}\ln \left| {{{2\cos x + \sin x} \over {2\cos x - \sin x}}} \right| + C$ B: ${1 \over 4}\ln \left| {{{2\cos {x \over 2} + \sin {x \over 2}} \over {2\cos {x \over 2} - \sin {x \over 2}}}} \right| + C$ C: $\ln \left| {{{\cos {x \over 2} + \sin {x \over 2}} \over {\cos {x \over 2} - \sin {x \over 2}}}} \right| + C$ D: $\ln \left| {{{\cos x + \sin x} \over {\cos x - \sin x}}} \right| + C$
- 已知 \( y = \sin x + \ln 2 \),则 \( y' = \cos x + {1 \over 2} \)( ).
- 已知\( y = {x^{\cos x}} \) ,则\( y' = \left( { - \sin x\ln x + { { \cos x} \over x}} \right){x^{\cos x}} \)( ).
- 求函数$f(x)=x^{\sin x}$的导数 A: $x^{\cos x}$ B: $\sin (x) x^{\sin (x) -1}$ C: $x^{\sin x}(\cos x\ln x+\frac{\sin x}{x})$ D: $x^{\sin x}(\sin x\ln x+\frac{\cos x}{x}$
- 已知\( y = \ln (\sin x) \),则\( y' \)为( ). A: \( {1 \over {\sin x}} \) B: \( {1 \over {\cos x}} \) C: \( \cot x \) D: \( - \cot x \)