Question

Найти производную:

x=6cos((2П/0,2)t+45градусов)

Answer 1

$x=6\, cos(\frac{2\pi }{0,2}\, t+45^\circ )=6\, cos(10\pi \cdot t+\frac{\pi}{4})\\\\\boxed {(cosu)'=-sinu\cdot u'}\\\\\frac{dx}{dt}=6\cdot \Big ((-sin(10\pi \cdot t+\frac{\pi}{4})\Big )\cdot 10\pi =-60\pi \cdot sin(10\pi \, t+\frac{\pi}{4})$