Question

help with question 15
finding the period and
also letter c)
-- see attached file

Answer 1

all your doing is reading the graph.... which question in #15?

Answer 2

so i know that the period ends at 5(pi)
... but then the back of the book says the period is 5(pi)/2

Answer 3

what part is this question you referring to?

Answer 4

oh number 15b)

Answer 5

do you know the definition of period (of a periodic function)?

Answer 6

the period of the graph is the horizontal length of one cycle in the graph

Answer 7

yes...
so if we start at x=0... it goes down, then up, crosses the x axis then comes back down to the x axis... that is 1 cycle of the graph. notice this occurs at 2.5pi...

so your period is 2.5pi or (5/2)pi

Answer 8

what you did when you went to 5pi is you actually went through 2 cycles of the graph...

Answer 9

oh cause if you look at the end of the graph the length of the bottom line ... it looks shorter that the rest

Answer 10

hey, you're right!!!

Answer 11

good eye!... hmmm... i wonder if it's a misprint on the graph since the answer is the one i thought the book has....

Answer 12

it might be. this book has a lot of typos and mistakes. haha.
but i do see what you were telling me. thank you :)

Answer 13

good job alexeis... :)

Answer 14

and yw... :)