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    10c
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    I've said that assuming u>0 then if direction were changed then the speed of P \dfrac{u}{2}(5-3e)<0 \text { which leads to } e >\dfrac{5}{3} which can't be true as 0 \leq e \leq  1 .

    Is this fine?

    Thanks

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    (Original post by Kvothe the arcane)
    Part c

    I've said that assuming u>0 then if direction were changed then the speed of P \dfrac{1}{2}(5-3e)\dfrac{5}{3} which can't be true as 0 \leq e \leq  1 .

    Is this fine?

    Thanks

    Sent from my SM-G925F using Tapatalk
    Looks fine. Can u post the question ?
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    (Original post by Duke Glacia)
    Looks fine. Can u post the question ?
    Thanks . Pleaze see edit.
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    (Original post by Kvothe the arcane)
    Thanks . Pleaze see edit.
    Yup perfect.

    Lovely handwriting btw
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    (Original post by Kvothe the arcane)
    I've said that assuming u>0 then if direction were changed then the speed of P \dfrac{u}{2}(5-3e)<0 \text { which leads to } e >\dfrac{5}{3} which can't be true as 0 \leq e \leq  1
    I'm not sure if yours sufficiently shows it or not, but this is how I'd do it:

    \displaystyle 0 \leq \mathrm{e} \leq 1 \Rightarrow u \leq \mathbf{v}_{\text{p}}\leq \frac{5u}{2} \Rightarrow \mathbf{v}_{\text{p}}> 0
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    (Original post by Kvothe the arcane)
    ...
    It's a bit... weird.

    It'd be better to say that since 0 \leq e \leq 1, then \frac{u}{2} (5-3e) > 0. i.e: a direct proof is easily found here so using an indirect one (contradiction) feels off.
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    (Original post by Duke Glacia)
    Yup perfect.

    Lovely handwriting btw
    Thanks. It's okay but at least it's legible .

    (Original post by Ayman!)
    I'm not sure if yours sufficiently shows it or not, but this is how I'd do it:

    \displaystyle 0 \leq \mathrm{e} \leq 1 \Rightarrow u \leq \mathbf{v}_{\text{p}}\leq \frac{5u}{2} \Rightarrow \mathbf{v}_{\text{p}}> 0
    That makes sense :yep:. Thanks.

    (Original post by Zacken)
    It's a bit... weird.

    It'd be better to say that since 0 \leq e \leq 1, then \frac{u}{2} (5-3e) > 0. i.e: a direct proof is easily found here so using an indirect one (contradiction) feels off.
    I see. Fair enough. That's what made sense to me at the time so I'm glad I posted . Thanks.
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    (Original post by Kvothe the arcane)
    Thanks.
    Cheers.
 
 
 
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