LittlerCandy
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I'm not 100% on this one. I integrated the displacement equation I'd gotten from (iii) but then I subtracted the integration of the line y=5. Did anyone else do this? If not, what was the correct answer?
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What was the answer for 14(a)(iv)? (1 Viewer)
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Recondit
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Correct answer was 29m
Youre meant to integrate the v(t) function as this gives displacement (however you have to absolute value the area under the x-axis to give distance)
In simpler terms, Just draw v=10-2t on a graph from t=0 (v=10) to t=7 (v=-4) with t-int (v=0) at t=5
Then find area of triangle from t=0 to t=5 which is ABOVE the x-axis which is 25u2 then find the area below the x-axis between t=5 to t=7 which is 4u2
Sum of areas is 29u2 therefore 29m total distance travelled
Youre meant to integrate the v(t) function as this gives displacement (however you have to absolute value the area under the x-axis to give distance)
In simpler terms, Just draw v=10-2t on a graph from t=0 (v=10) to t=7 (v=-4) with t-int (v=0) at t=5
Then find area of triangle from t=0 to t=5 which is ABOVE the x-axis which is 25u2 then find the area below the x-axis between t=5 to t=7 which is 4u2
Sum of areas is 29u2 therefore 29m total distance travelled
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Menomaths
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Shazer2
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Got 29m. I just did table of values for 0 to 7, and showed the distance travelled. Reckon I'll get marks?
Recondit
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My friend did something similar to that... I think you should get itGot 29m. I just did table of values for 0 to 7, and showed the distance travelled. Reckon I'll get marks?
Menomaths
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That's the correct answer and you showed working, better than mine (which was just adding up the differences LOL) so you should get full marks for it.Got 29m. I just did table of values for 0 to 7, and showed the distance travelled. Reckon I'll get marks?
Recondit
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lOl I actually got this question wrong cos I calculated area under x-axis wrong
LittlerCandy
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So what was the method exactly??
Just saw the method above, my bad.
Just saw the method above, my bad.
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lolwot
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Menomaths
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You're not the only one lol
Recondit
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Did you get 39m? LOL same here with second comment
lolwot
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i got 21
did it from 7 to 0 so it was like 25 + (-4), instead of 0 to 5 and 5 to 7
LittlerCandy
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Thanks, this is the method I attempted. Poorly attempted I might add
NFmusic1995
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i got 29, i did it manually from each second and hoping it wouldnt go backwrds withina decimal otherwise the method wouldnt work LOL