Question

Производная функции f (x )= 4cosx×5ctgx

Answer 1

$f(x)=4cosx*5ctgx \ \ f'(x)=(4cosx)'*5ctgx+4cosx*(5ctgx)'=-4sinx*5ctgx+4cosx* \ \ *(- frac{5}{sin^2x} )=-20sinx*ctgx- frac{20cosx}{sin^2x}$

Answer 2

описка -20sinx*cosx - 20cosx / sin²x

Answer 3

Производная функции f (x )= 4cosx×5ctgx.
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 f (x )= 4cosx*5ctgx = 20cosx*ctqx
f `(x )=  (20cosx*ctgx) ` = 20*(cosx*ctgx)`=20*( (cosx) ` *ctqx +cosx*(ctqx) `) =
20*(-sinx *ctqx  - cosx/sin²x )  = - 20cosx(1 +1/sin²x) .