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    i am so stuck on this question
    i've done questions like this before but it would say with limits

    ---Moved to Maths---
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    I am talking about B NOT A
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    RDKGames
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    (Original post by mervin101)
    RDKGames
    The trapezium rule says that \displaystyle \int_a^b f(x) .dx \approx \frac{h}{2}[y_0+y_n + 2(y_1+y_2+...+y_{n-1})] where h=\frac{b-a}{n} and n is the amount of strips.

    With this question, it is asking you to use the table to compute the approximation and you can see that h=0.5 here.

    Then y_1=f(x_1)=f(1)

    and y_2=f(x_2)=f(1.5)

    and so on...

    What is confusing?
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    (Original post by RDKGames)
    The trapezium rule says that \displaystyle \int_a^b f(x) .dx \approx \frac{h}{2}[y_0+y_n + 2(y_1+y_2+...+y_{n-1})] where h=\frac{b-a}{n} and n is the amount of strips.

    With this question, it is asking you to use the table to compute the approximation and you can see that h=0.5 here.

    Then y_1=f(x_1)=f(1)

    and y_2=f(x_2)=f(1.5)

    and so on...

    What is confusing?
    what is n?
    i dont know how h = 0.5
    4-1/ n
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    (Original post by mervin101)
    what is n?
    i dont know how h = 0.5
    4-1/ n
    h is the strip width, so the fixed change in x. Which is 0.5. Just look at the x-values from the table, they all change by 0.5 as you count on.
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    (Original post by RDKGames)
    h is the strip width, so the fixed change in x. Which is 0.5. Just look at the x-values from the table, they all change by 0.5 as you count on.
    h= b-a divided by n

    b-a = 3 (4-1) now i divide by n to get h

    i'm still confused about n
    i understand h is the strip width

    do i rearrange or am i missing something
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    (Original post by mervin101)
    h= b-a divided by n

    b-a = 3 (4-1) now i divide by n to get h

    i'm still confused about n
    i understand h is the strip width

    do i rearrange or am i missing something
    You don't need to find n. You only need it to find h in these types of questions but you have h from the get-go...
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    (Original post by RDKGames)
    You don't need to find n. You only need it to find h in these types of questions but you have h from the get-go...
    can you use this formula?

    width of strip/2 x 1st height + sum of middle heights + last height?
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    (Original post by mervin101)
    can you use this formula?

    width of strip/2 x 1st height + sum of middle heights + last height?
    No because it's not quite the same as

    (half the strip width) multiplied by (1st height + last height + 2 lots of the sum of the middle heights)

    if you want the formula in words.
 
 
 
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