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FP1 Calculus URGENT HELP please! Watch

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    Q3 is from FP1 Calculus...have no idea how to do it since I got two 'problem values' here

    Need help please!!!
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    I've only just finished learning FP1, and this is how I would go about it Replace the infinity with 'a', then integrate as normal. As 'a' tends towards infinity, the integral also tends towards infinity! As I said I'm also just a student so let me know if anyone disagrees
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    (Original post by Oliviazh)
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    Q3 is from FP1 Calculus...have no idea how to do it since I got two 'problem values' here

    Need help please!!!
    Integrate as normal. When it comes to substituting limits, you cannot substitute \infty because it is not a number. Instead, you assign a different variable, such as a, and take the limit of the integral as a\rightarrow \infty
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    (Original post by RDKGames)
    Integrate as normal. When it comes to substituting limits, you cannot substitute \infty because it is not a number. Instead, you assign a different variable, such as a, and take the limit of the integral as a\rightarrow \infty
    But how about 0? Cuz my teacher also said that we need to replace 0 with a different variable.... that's why I'm confused cuz it then will be two variables😂
    Or is it in this case we don't need to consider 0?
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    (Original post by Oliviazh)
    But how about 0? Cuz my teacher also said that we need to replace 0 with a different variable.... that's why I'm confused cuz it then will be two variables😂
    Or is it in this case we don't need to consider 0?
    Well technically speaking the function \frac{1}{\sqrt{x}} is undefined at x=0 so you would need to replace it as well, but personally I would skip this because the integrated function will be defined at x=0.

    If it was \displaystyle \int_0^{\infty} x^{-3/2} or something then you would indeed need to replace the 0.
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    (Original post by RDKGames)
    Well technically speaking the function \frac{1}{\sqrt{x}} is undefined at x=0 so you would need to replace it as well, but personally I would skip this because the integrated function will be defined at x=0.

    If it was \displaystyle \int_0^{\infty} x^{-3/2} or something then you would indeed need to replace the 0.
    Thanks a lot!
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    (Original post by spoiler-s)
    I've only just finished learning FP1, and this is how I would go about it Replace the infinity with 'a', then integrate as normal. As 'a' tends towards infinity, the integral also tends towards infinity! As I said I'm also just a student so let me know if anyone disagrees
    Thank you!
 
 
 
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