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anonymous

  • one year ago

What is the discontuinty of f(x) = the quantity negative x squared plus x plus 20 over the quantity x plus 4?

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  1. anonymous
    • one year ago
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    @Astrophysics

  2. anonymous
    • one year ago
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    |dw:1437190829325:dw|

  3. anonymous
    • one year ago
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    So I think it is -4?

  4. anonymous
    • one year ago
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    Am I right?

  5. Astrophysics
    • one year ago
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    So you're taking \[\lim_{x \rightarrow -4} f(x)\]

  6. anonymous
    • one year ago
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    Um..I suppose:).

  7. Astrophysics
    • one year ago
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    Mhm, you know calculus?

  8. anonymous
    • one year ago
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    No. It's Algebra 2

  9. Astrophysics
    • one year ago
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    But yes, that's right -4

  10. Astrophysics
    • one year ago
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    As the domain is all real numbers where x cannot equal -4.

  11. Astrophysics
    • one year ago
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    So you're looking for what x is basically then, so factor the top, that should give it away :)

  12. Astrophysics
    • one year ago
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    To find the zeros you have to factor the numerator, it's just finding the roots, hence x.

  13. anonymous
    • one year ago
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    So (x-4)(x+5)

  14. anonymous
    • one year ago
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    do I just plug in -4?

  15. Astrophysics
    • one year ago
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    You should've got -(x+4)(x-5)

  16. anonymous
    • one year ago
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    So it is (-4,1)

  17. Astrophysics
    • one year ago
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    Then you can cancel out the numerator and denominator of (x+4) and you'll have x = 5 as your zero

  18. anonymous
    • one year ago
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    So, if I were to graph it, the point would be -4,1 ? Correct?

  19. anonymous
    • one year ago
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    Is it working now?

  20. Astrophysics
    • one year ago
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    Oh I see what you mean now, so if we take the limit we would indeed get = 9

  21. Astrophysics
    • one year ago
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    I really can't remember doing it in algebra 2, mhm I will have to do some research

  22. anonymous
    • one year ago
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    haha<3 Ok! Thank-you:)

  23. anonymous
    • one year ago
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    What is the graph of the function f(x) = the quantity of negative x squared minus 2 x minus 2, all over x minus 2?

  24. Astrophysics
    • one year ago
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    use this site to graph https://www.desmos.com/calculator

  25. anonymous
    • one year ago
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    I don't mean to post another question because usually I can figure things out by myself, but I can't graph usind desmos. It won't work

  26. anonymous
    • one year ago
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    Maybe I'm doing it wrong. Because when I typed it in, I only got one graph when it should have been two. Like 2 lines:)

  27. anonymous
    • one year ago
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    Any thoughts?

  28. Astrophysics
    • one year ago
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    Well, you can't put words if that's what you're trying, so what do those words tell us mathematically?

  29. anonymous
    • one year ago
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    -x^2-2x-2/x-2

  30. anonymous
    • one year ago
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    And I didn't :) I typed in that

  31. Astrophysics
    • one year ago
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    I got this, make sure you put y = , or f(x) = |dw:1437192565745:dw|

  32. anonymous
    • one year ago
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    Ok:) But shouldn't there two?

  33. anonymous
    • one year ago
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    Nevermind! Thank-you<3

  34. Astrophysics
    • one year ago
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    Np ^.^

  35. anonymous
    • one year ago
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    \[A\ function\ f(x)\ is\ said\ tobe\ continuous\ at\ a\ point\ x=c \ of\ its\ domain\\ \iff\ \lim_{x \rightarrow c}=f(c).\]

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