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    Hey Guys

    I need help with two math questions.

    1.3sinx+1=4.8 , 0<x<2π

    2. f(x)= x+1 0≤ x<2
    4x-10 2≤x≤5
    15-3x 5<x≤6
    plot a graph of this function, stating its domain and range
    evaluate f(0), f(4) and f(6)

    Thank you so much for the help I would really appreciate it.
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    (Original post by YogieBear1001)
    Hey Guys

    I need help with two math questions.

    1.3sinx+1=4.8 , 0<x<2π

    2. f(x)= x+1 0≤ x<2
    4x-10 2≤x≤5
    15-3x 5<x≤6
    plot a graph of this function, stating its domain and range
    evaluate f(0), f(4) and f(6)

    Thank you so much for the help I would really appreciate it.

    No problem

    Let's start with Q1

    What help do you need
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    (Original post by TenOfThem)
    No problem

    Let's start with Q1

    What help do you need
    Thank you so much

    Q1 is 3sinx+1=4.8 , 0<x<2π
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    (Original post by YogieBear1001)
    Thank you so much

    Q1 is 3sinx+1=4.8 , 0<x<2π
    Yes, I saw

    What help do you need

    How far have you got
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    (Original post by TenOfThem)
    Yes, I saw

    What help do you need

    How far have you got
    3sinx+1=4.8 , 0<x<2π

    I think im calculating it all wrong, but this bit --->+1=4.8 , 0<x<2π is confusing me.
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    (Original post by YogieBear1001)
    3sinx+1=4.8 , 0<x<2π

    I think im calculating it all wrong, but this bit --->+1=4.8 , 0<x<2π is confusing me.
    subtract 1

    So you have 3Sinx=3.8
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    (Original post by YogieBear1001)
    3sinx+1=4.8 , 0<x<2π

    I think im calculating it all wrong, but this bit --->+1=4.8 , 0<x<2π is confusing me.
    I see TenOfThem's offline, so I'll try and help.
    Is this the correct question? As I'm fairly sure the only solutions are complex. . .
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    (Original post by joostan)
    I see TenOfThem's offline, so I'll try and help.
    Is this the correct question? As I'm fairly sure the only solutions are complex. . .
    Thank you
    yes it is
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    (Original post by YogieBear1001)
    Thank you
    yes it is
    Do you know about sinh(x) and complex numbers?
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    The angles are in radians; 2pi = 360 deg

    3sinx+1=4.8
    3sinx=3.8
    sinx=3.8/3
    sin-1(3.8/3) =

    The rest is to you.
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    (Original post by m-s-96)
    The angles are in radians; 2pi = 360 deg

    3sinx+1=4.8
    3sinx=3.8
    sinx=3.8/3
    sin-1(3.8/3) =

    The rest is to you.
    Oh Yes! Thank you so much
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    (Original post by YogieBear1001)
    Oh Yes! Thank you so much
    No problem.
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    (Original post by YogieBear1001)
    Hey Guys

    I need help with two math questions.

    1.3sinx+1=4.8 , 0<x<2π
    You're going to have a problem with that!

    As x varies between 0 and 2pi, sinx takes on values from -1 to +1 so the max value of 3sin x is 3 and the max value of 3sin x + 1 is 4 - you can never reach 4.8 with real values of x!
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    (Original post by davros)
    You're going to have a problem with that!

    As x varies between 0 and 2pi, sinx takes on values from -1 to +1 so the max value of 3sin x is 3 and the max value of 3sin x + 1 is 4 - you can never reach 4.8 with real values of x!
    Thank you!
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    (Original post by davros)
    You're going to have a problem with that!

    As x varies between 0 and 2pi, sinx takes on values from -1 to +1 so the max value of 3sin x is 3 and the max value of 3sin x + 1 is 4 - you can never reach 4.8 with real values of x!
    The value for 'x' stated in the question represents the angle, not the value after applying sin.

    Yes you are correct, sin only takes -1 to +1 and therefore 3sin + 1 is -4 to 4

    :P
 
 
 
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