Question

0<=t<=5. find when t(cost)>0

Answer 1

You have
(t)(cost)>0
t>0
and
cos(t)>0
t>arccos(0)
t>90
t>270

Answer 2

howd you go from 90 to 270? @.Sam.

Answer 3

you should look for the domain of cost for which cos t >0

Answer 4

ie from \[-\pi/2 -\pi /2\]

Answer 5

so thats the answer?

Answer 6

ya

Answer 7

because cos(0)=90, then the 270 comes from
so,
360-90= 270