Mikä on f (theta) = sin 2 t - cos 5 t: n taajuus?

Vastaus:

# 2pi #

Selitys:

Sin 2t -> aika # (2pi) / 2 = pi #

Cos 5t -> -aika# (2pi) / 5 #

F (t) -> vähiten yleinen kerta #pi ja (2pi) / 5.#

pi …………. x 2 … -> 2pi

(2pi) / 5 …. x 5 ……>> 2pi

F (t) -aika on # (2pi) #

Vastaus:

Taajuus on # = 1 / (2pi) #

Selitys:

Taajuus on # F = 1 / T #

Aika on # = T #

Toiminto #F (theta) # on T-jaksollinen iif

#f (theta) = (theeta + T) #

Siksi, #sin (2t) -cos (5t) = sin2 (t + T) -cos5 (t + T) #

Siksi, # {(sin (2t) = sin2 (t + T)), (cos (5t) = cos5 (t + T)):} #

#<=>#, # {(Sin2t = sin (2t + 2T)), (cos5t = cos (5t + 5T)):} #

#<=>#, # {(Sin2t = sin2tcos2T + cos2tsin2T), (cos5t = cos5tcos5T-sin5tsin5T):} #

#<=>#, # {(Cos2T = 1), (cos5T = 1):} #

#<=>#, # {(2T = 2pi = 4pi), (5T = 2pi = 4pi = 6pi = 8pi = 10pi):} #

#<=>#, # {(T = 4 / 2pi = 2pi), (T = 10 / 5pi = 2pi):} #

Aika on # = 2pi #

Taajuus on

# F = 1 / (2pi) #

kuvaaja {sin (2x) -cos (5x) -3,75, 18,75, -7,045, 4,205}