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Math Help - SOLVE FOR X with a sinx in it

  1. #1
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    SOLVE FOR X with a sinx in it

    The question asks
    "If f(x)= x + 10*sin(x), show that there is a number c such that f(c)=1000"

    so its asking to solve for x when f(x)=1000 right?
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  2. #2
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    Quote Originally Posted by colmex View Post
    The question asks
    "If f(x)= x + 10*sin(x), show that there is a number c such that f(c)=1000"

    so its asking to solve for x when f(x)=1000 right?
    Solving for x would be a proof
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  3. #3
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    Quote Originally Posted by colmex View Post
    The question asks
    "If f(x)= x + 10*sin(x), show that there is a number c such that f(c)=1000"

    so its asking to solve for x when f(x)=1000 right?
    Not exactly.

    The problem is asking you to show a solution exists, but it does not ask you to find it.

    Sometimes it is easy to show the existence of a solution but hard to actually find the solution. If you can find a solution, great-- that certainly proves its existence.
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  4. #4
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    ohhhhhhhhhhhh okay
    so how do i prove it? haha
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  5. #5
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    Quote Originally Posted by colmex View Post
    ohhhhhhhhhhhh okay
    so how do i prove it? haha
    Use the Intermediate Value Theorem.
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