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    (Original post by Mr M)
    Minimum = smallest

    Maximum = biggest

    What is the smallest y value the sin x graph takes and at what x value does this occur?

    Edit: I used the words lowest and smallest deliberately so that you would be able to answer my question previously.
    Min. y=-1 x=1.98
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    (Original post by Blackfyre)
    Min. y=-1 x=1.98
    Ok the minimum y value of -1 is correct but I have no idea where you got that x value from.

    Can you take a look at the diagram I added to my previous post?
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    (Original post by Mr M)
    Ok the minimum y value of -1 is correct but I have no idea where you got that x value from.

    Can you take a look at the diagram I added to my previous post?
    My bad I plugged it in the fraction.
    x~4.7
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    (Original post by Blackfyre)
    My bad I plugged it in the fraction.
    x~4.7
    Ok now you are working in radians but you said the question requires degrees. The answer would have been \frac{3 \pi}{2} in radians (don't use decimals for questions like this).

    I have attached a diagram in degrees in post 19. Could you look at it please?
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    We are nearly at the end now.

    Take your lowest value for sin x and substitute it into this formula to find the greatest possible value of f(x):

    \displaystyle f(x)=\frac{4}{2+\sin x}

    Edit: I hope you will understand why picking the lowest value for sin x makes the largest value for f(x). You are dividing a positive number by a smaller positive number to produce the largest possible answer.
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    (Original post by Mr M)
    We are nearly at the end now.

    Take your lowest value for sin x and substitute it into this formula to find the greatest possible value of f(x):

    \displaystyle f(x)=\frac{4}{2+\sin x}

    Edit: I hope you will understand why picking the lowest value for sin x makes the largest value for f(x). You are dividing a positive number by a smaller positive number to produce the largest possible answer.
    I'm checking the graph in degrees, does x equal 3 there? In this case x=1.94

    Or I should transform 4.7 into degrees: 4.7*180/pi = 269.29

    x=3.99
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    (Original post by Blackfyre)
    I'm checking the graph in degrees, does x equal 3 there? In this case x=1.94

    Or I should transform 4.7 into degrees: 4.7*180/pi = 269.29

    x=3.99
    270 is the answer. Again you are working in decimals after I told you not to. If you start to listen more carefully to what I am saying you will find this easy.

    The number 270 can just be read from the diagram I asked you to look at twice.



    Right now look at my last post and you will have answered the question.
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    (Original post by Mr M)
    270 is the answer. Again you are working in decimals after I told you not to. If you start to listen more carefully to what I am saying you will find this easy.

    The number 270 can just be read from the diagram I asked you to look at twice.



    Right now look at my last post and you will have answered the question.
    Thanks a lot for your time Mr M, I understand now that x is 270 and when you plug it in equation you get the value of 4. This was really helpful much appreciated, I'll try to find more similar problems so I can improve myself.

    So otherwise if I was asked for a minimum value then y=1 x=90, minimum value of f(x) 4/3

    Edit: it might seem like trolling but it's pure stupidity of a foreign student who moved to Britain this year.
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    (Original post by Blackfyre)
    Thanks a lot for your time Mr M, I understand now that x is 270 and when you plug it in equation you get the value of 4. This was really helpful much appreciated, I'll try to find more similar problems so I can improve myself.

    So otherwise if I was asked for a minimum value then y=1 x=90, minimum value of f(x) 4/3

    Edit: it might seem like trolling but it's pure stupidity of a foreign student who moved to Britain this year.
    Ah ok. I'm glad you got there in the end! And yes, that is the minimum value of f(x).
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    Again Mr. M thanks a lot for all the help, I was able to master well C1 because of this community and the same thing is happening with C2.
 
 
 
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