A community for students.
Here's the question you clicked on:
 0 viewing
tkachenko
 2 years ago
i need a little help
tkachenko
 2 years ago
i need a little help

This Question is Open

tkachenko
 2 years ago
Best ResponseYou've already chosen the best response.0Use a graphing calculator to solve the equation in the interval from 0 to 2. Round to the nearest hundredth. 7 cos 2t = 3

tkachenko
 2 years ago
Best ResponseYou've already chosen the best response.0i need it step by step to understand it

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8just type in 7* cos (2x) and where the graph crosses 3 is your answer. Make sure you in radians. Or degrees depends on what your q asks.

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8here it is when i pasted it to google.

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8idk about that with google i got .64

tkachenko
 2 years ago
Best ResponseYou've already chosen the best response.0what about this one The water level varies from 12 inches at low tide to 52 inches at high tide. Low tide occurs at 9:15 a.m. and high tide occurs at 3:30 p.m. What is a cosine function that models the variation in inches above and below the water level as a function of time in hours since 9:15 a.m.?

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8use function manipulation

tkachenko
 2 years ago
Best ResponseYou've already chosen the best response.0step bu step if you could

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8ok lets see if we can do this start with the graph of sin x dw:1356583876231:dw Lets see if we can manipluate it.

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8the rules are a*sin (x) a streches it up and down 1/a sin (x) shrinks it. a+sin(x) shifts it up a+sin(x) shifts it down sin(x+a) shifts to the left TO the LEFT now lets combine those rules.

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.81 if you with me so far lets start The water level varies from 12 inches at low tide to 52 inches at high tide 5212= 40 this gives us our amplitude which is difference so we get this 40*sin(x) http://tinyurl.com/dyqaluu <graph but we want half of that cuzz of this dw:1356585003441:dw so now we have 20*sin(x) 2 now we shift it up before i shift it up are you with me so far? there are a few more steps. shifting up and shifting left.

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.82 shifting up so far we have this http://tinyurl.com/dyqaluu 20*sin(x) If you look at it the low point aka low tide is at 20 put we want it at +12 so we have shift up by an unknown amount we set up this equation 20+x=12 in my mind i read it as add x to 20 till you get 12 x=32 so now we have 20*sin(x)+32 with me so far. notice it getting more and more looking like our wanted graph now we shift left and right. With me so far? http://tinyurl.com/cpcmz73 graph

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8according to your info 3:30 is high tide. we can call that 3.5

tkachenko
 2 years ago
Best ResponseYou've already chosen the best response.0so whats the next step to this problem

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8Using 20*sin(x)+32 we have to get the hide tide to occur at 3.5 we shift it 20*sin(xa)+32

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8ooh i noticed i messed up a bit by using sin. Using cos will be easier cuzz the amplitude is right at 0 hour dw:1356585955086:dw

tkachenko
 2 years ago
Best ResponseYou've already chosen the best response.0so should i erase sin and use cos

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8so just shift to right 3.5 so final answer is 20*cos(x3.5)+32 ^ remember adding actually shifts to the left and subtracting shift right :)

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8yes use cos. Cos is nothing but sin shifted a certain amount to the left or right so that the coordinant of is 0,1 not 0,0

tkachenko
 2 years ago
Best ResponseYou've already chosen the best response.0so 20*cos(x3.5)+32 is the final answer

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8yup did you understand? :)

tkachenko
 2 years ago
Best ResponseYou've already chosen the best response.0yes thank you very much for all that help

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8let me know if it is correct

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8fan me so you dont lose touch. I am really interested in this problem. Have not done it in years. I am 99.99999999% sure it is right but since i have not done it in a while. there is still that .0000000000001% possibility i am rusty :D

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8there is also the odds that i need to stretch it horisontally

timo86m
 2 years ago
Best ResponseYou've already chosen the best response.8oh yup you do have to stretch dw:1356587327217:dw
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.