In x
X, In x - xdn x 2xln x - x
Irvx
cosx 2* Irvx
c x 2 x( - sin x 2* In 2) - 3(cosx 2) In x -x“= sin x in x - x^sin x - in x - x,s s x(-? 2x) -( x - x,)c x x sin x cosxln x s x x3 ? s x x,8 3,(cosx 2x)-(sinx x,)8ln3 3A = 3“ (8) y = e-tan x In x 解 y = ie-tan x e?tan x In x = e?tan x 2 2.求下列函数的导数y: 解:y' = (e、?)= (e * x) x 2 2 2、x (2) y = In cosx e , 1 —.一、 sinx ... 解:y = ------------- (—sinx)= -------------- = —tanx cosx cos i (3) y = . x x x Ff 7 解:y = x8 =— 8 )8 仞y = sirvx 解:y = 2sin x sinx = 2sin x cosx = 2sin2x (5) y = sin x cos x x I o 解: y =cosx2 2x = 2xcosx xcose 2 2 2 解: y srsinex ex =- 2xex sine (7) y =sin -x cos nx y = sin-x cosnx sin-x cosnx =ns xc xc nx-ns xs nx) 5sin x n-f n 解:y' =5-ln5 cosx =ln 5cosx5- cosx (9)y = e cosx 解:V = e - sinx ...sinxeC0SX 3.在下列方程中,y = y(x)是由方程确定的函数,求y*: (1) y cosx = s 2y. y sin x y cosx-2e^ 解 y cosx - ysin x = 2e y =cos yin x ? 1 y = sin y.y In x cosy.— x y “ : 、 cosy x(1 sin y In x) 解 . , ,J (3) 2xsin y = y 解:2xc cy.ys 2s iy n y= 2xy_-2ysiny 2xy co g x 2 2 =x In y 0 y° 醉 y = - 1 : y x e? = y(o)ln , 解:-e,y = 2yyx ..- (6) y?1 = esin y 解:2yy =e*cosy.y sin y.ey、 y x 2 h 解:e y = e_3y y 2yx- X,琴-2siny y (2xcosy y y — x(2y-e0 v e-sin y 2y-e cosy e -2 y3y e