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    I would really appreciate it if somebody would help me finish the M2 projectiles chapter.
    https://6caf30cbcaf0c74dfdacf3d63c55...EZJY1U/CH1.pdf
    So the first Question- (just to get started)...
    Exercise B Q 10.- Did they make a mistake in part C? (they also give roots of velocity eqn below answer). I think they made a huge mistake :/
    Thanks!
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    Do it yourself

    Show your working and proof of what youve done
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    (Original post by schindlers list)
    Do it yourself

    Show your working and proof of what youve done
    omg I have. I did not get the answer of 42 which it is supposed to be.
    Integral of velocity eqn is S= t^{3} -6t^{2} +5t
    I put in values for 4 and the root and then the integral from the root to 3. I got a really small answer... :/
    If you look at the solution bank it gives incorrect roots (geogebra agrees) and in reality the velocity does change sign...
    The question asks for distance travelled in the interval [3,4] - so it means you mod the negative integral value (for 1 of the integrals). Correct me if I'm wrong.
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    bump
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    (Original post by MathMeister)
    omg I have. I did not get the answer of 42 which it is supposed to be.
    Integral of velocity eqn is S= t^{3} -6t^{2} +5t
    I put in values for 4 and the root and then the integral from the root to 3. I got a really small answer... :/
    If you look at the solution bank it gives incorrect roots (geogebra agrees) and in reality the velocity does change sign...
    The question asks for distance travelled in the interval [3,4] - so it means you mod the negative integral value (for 1 of the integrals). Correct me if I'm wrong.
    No

    Show the working so lying
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    (Original post by schindlers list)
    No
    Show the working so lying
    I have kind of given lots of info/ working./proof I just wanna know if they are wrong or not! I cannot find that out :/
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    bump... come on guys/gals
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    (Original post by MathMeister)
    bump... come on guys/gals
    I was trolling

    I dont know none of these lol
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    (Original post by schindlers list)
    I was trolling shodd of then off yeh pop
    I dont know none of these lol
    ha yah I know
    twas why i was asking others lol
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    (Original post by MathMeister)
    ha yah I know
    twas why i was asking others lol
    It does seem like they've made a mistake.

     4^3-(6 \times 4^2)+20 = 64-96+20 = -12 \not= -60
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    (Original post by ThatPerson)
    It does seem like they've made a mistake.

     4^3-(6 \times 4^2)+20 = 64-96+20 = -12 \not= -60
    I do not know how to do it. Plz may somebody help me get the correct answer?
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    (Original post by ThatPerson)
    It does seem like they've made a mistake.

     4^3-(6 \times 4^2)+20 = 64-96+20 = -12 \not= -60
    Is the answer the integral of the velocity eqn from 4 to the root where v changes sign. plus the mod of the integral from the root to 3?
    I got 2.256902162 metres ???
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    (Original post by MathMeister)
    Is the answer the integral of the velocity eqn from 4 to the root where v changes sign. plus the mod of the integral from the root to 3?
    I got 2.256902162 metres ???
    I can't quite follow what you've written there but I believe the correct answer is 2.26m.
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    (Original post by ThatPerson)
    I can't quite follow what you've written there but I believe the correct answer is 2.26m.
    Ahhh ok Thanks I surely got it right then- our method then is correct
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    (Original post by ThatPerson)
    I can't quite follow what you've written there but I believe the correct answer is 2.26m.
    still doesnt solve why one of my quadratics in another question ended in an imaginary number for T lol
    Correct eqn and everything cus it worked when changed into linear eqn haha
 
 
 
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