#Sinusoidal trig question type

26 messages · Page 1 of 1 (latest)

worldly finch
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The (0,64) and (3,84) number at Lana represent the numbers on the red graph, the bottom is (0,64) and top is (3,84) if u didn’t know

The models I found for Lana is

Lana is y=10sin(pi/3(x-1.5))+70

The QUESTIONs is to find what time interval they both are higher than 70db in 15 minutes

The blank white page is an example of a way to solve it

IMG_6149.png IMG_6147.png IMG_6145.png IMG_6155.png
dawn lotusBOT
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hybrid raven
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Oh, why are they solving it in such a way... Why write out so many digits?

worldly finch
worldly finch
hybrid raven
worldly finch
hybrid raven
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Ah, so this is confirmed to be correct. Alright.

worldly finch
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From my calculation if it’s wrong tho I’ll try to work again

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The question is to find what time interval she sings louder than 70db

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Which is what I am stuck on
I am on the general solution now where I solve for x when n = 0,1,2,3

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But I don’t know what to do next all I got is this photo

IMG_6156.png
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Which is a similar question

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Not the same question same work out tho

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Forgot bottom part

IMG_6156.png
hybrid raven
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So, we have:
I(L, t) = 10sin((π/3)(t - 3/2)) + 70 = 10sin((π/3)t - π/2) + 70 = -10cos((π/3)t) + 70
I(A, t) = 5sin((π/4)(t - 4)) + 70 = 5sin((π/4)t - π) + 70 = -5sin((π/4)t) + 70
And now we want to do two things, as far as I understand.

  1. Solve the system of inequalities:
    I(L, t) > 70
    I(A, t) > 70
  2. Assuming "softer" means "lower intensity", solve the inequality:
    I(A, t) < I(L, t)
worldly finch
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Yeah but I’m doing first question first which is to find what time interval they are higher than 70db during/in 15 minutes

worldly finch
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This is another similar question and work out

IMG_6159.png
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I’ll see what u mean tho

IMG_6160.png
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Also lana correct one should be

Y=10sin(pi/3(x-1.5))+70 and the desmos should be aroma mb

worldly finch
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+close

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# worldly finch +close
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