Question

what is the arc length when theta= pi/3 and the radius is 5 cm?
a. 10pi/3 cm
b. 16pi/3 cm
c. pi/3 cm
d. 5pi/3 cm

Answer 1

SOMEONE HELP MEEEE PLEASE D;

Answer 2

s = r*theta

Answer 3

s = 5*pi/3

Answer 4

I dont think I did it right, what answer did you get?

Answer 5

What answer did you get?

Answer 6

I guess d, Im not sure

Answer 7

what did you get?

Answer 8

D is correct. since arc length = radius * angle in radians

Answer 9

ok thank you. do you think you could help me with another?

Answer 10

sure

Answer 11

the function f(t)= 25 sin(pi/2t) +10 models the temperature of a periodic chemical reaction where t represent time in hours. What are the maximum and minimum temperatures of the reaction, and how long does the entire cycle take?

Answer 12

is is it f(t) = 25*sin((pi/2)*t) + 10, or f(t) = 25*sin((pi/2*t)) + 10

Answer 13

the first one

Answer 14

well. We know the sin function has values between -1 and 1.

Answer 15

And, since we have 25*sin(pi/2 * t) + 10, we know -15 <= f(t) <= 35

Answer 16

Do you see how we got that?

Answer 17

okay, so what do we do now? I understand how you got that but Im completely clueless with these types of problems ;(

Answer 18

all this problem is asking for is the range and the periodicity of f(t). We just stated the range, and now we must state the periodicity. Our independent variable, t, is scaled by pi/2. What does this mean? Basically, our function has a period twice as long as sin(t) would. Check out this site and play around with the applets towards the bottom to get a better idea of how to handle these questions. http://www.intmath.com/trigonometric-graphs/3-graphs-sin-cos-phase-shift.php

Answer 19

okay I will, so did you get an answer for this? I can give you the options if you want me to

Answer 20

can you at least tell me the maximum and minimum?

Answer 21

Sure, go ahead and list them. We've already stated the answer.

Answer 22

-15 <= f(t) <= 35

Answer 23

oh okay the answer was A! thank you. this is the same type of problem, can you please help? this is the last one
The function f(t)= 3 cos(pi/6t) +5 represents the tide in the Blastic Sea. It has a maximum of 8 feet when time (t) is 0 and a minimum of 2 feet. The sea repeats this cycle every 12 hours. After nine hours, how high is the tide?
a. 12 feet
b. 5 feet
c. 4.5 feet
d. 2.5 feet

Answer 24

it's not actually (pi/6t) its more like (pi/6) *t) like the other problem

Answer 25

Ok, so the idea here is relate 12 hours to the period of the function.

Answer 26

okay

Answer 27

Are the answers listed correct?

Answer 28

yeah

Answer 29

Its 5. Sorry for the delay. i must go now.

Answer 30

okay thank you so much!