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# C2 Maximum value of f(x) Watch

1. (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
2. (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?
3. (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
4. (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 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?
5. 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):

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.
6. (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):

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
7. (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.
8. (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.
9. (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).
10. 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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