若函数f(x)=e^xsinx,则此函数图像在点(4,f(4))处的切线的倾斜角为 A.π/2 B.0 C.钝角 D.锐角f'x=e^xsinx+e^xcosx在(4,f(4))处的切线的斜率是e^4(sin4+cos4)设倾斜角为a,则有tana=e^4(sin4+cos4)a=arctan[e^4(sin4+cos4)]

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若函数f(x)=e^xsinx,则此函数图像在点(4,f(4))处的切线的倾斜角为 A.π/2 B.0 C.钝角 D.锐角f'x=e^xsinx+e^xcosx在(4,f(4))处的切线的斜率是e^4(sin4+cos4)设倾斜角为a,则有tana=e^4(sin4+cos4)a=arctan[e^4(sin4+cos4)]
若函数f(x)=e^xsinx,则此函数图像在点(4,f(4))处的切线的倾斜角为 A.π/2 B.0 C.钝角 D.锐角
f'x=e^xsinx+e^xcosx
在(4,f(4))处的切线的斜率是e^4(sin4+cos4)
设倾斜角为a,则有tana=e^4(sin4+cos4)
a=arctan[e^4(sin4+cos4)]

若函数f(x)=e^xsinx,则此函数图像在点(4,f(4))处的切线的倾斜角为 A.π/2 B.0 C.钝角 D.锐角f'x=e^xsinx+e^xcosx在(4,f(4))处的切线的斜率是e^4(sin4+cos4)设倾斜角为a,则有tana=e^4(sin4+cos4)a=arctan[e^4(sin4+cos4)]
tana=e^4(sin4+cos4)=tana=
=(根号2)e^4(sin[4+(pi)/4]
=(根号2)e^4(sin[pi-4-(pi)/4]
-(pi)/2

tana=e^4(sin4+cos4)=e^4sin(4+π/4)√2
4+π/4≈3π/2
sin(4+π/4)≈-1
e^4√2>1
∴tana<-1
所以是钝角.