General Thoughts: Mathematics (2 Viewers)

yma

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I got a concave down parabola with TP at 1 and roots at -2 and 3.
Don't know if that's right though. :s
You're probably right.. I got 2 upward concave in my graph.. my graph looks very weird


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WileyWanimal

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minimum s.p. at (-2,0) , max at (1, ...) and cuts x-axis at x = 3
well you have SPs where f'(x)=0, so surely the derivitive graph=0 where there were SPs on the original graph... Doesn't it?

idk, now I'm doubting myself.
 

orcevalm

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can anyone (if bothered) post the answers up for the MC ? i hope i got them right :/
 

chrisdelinet

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well you have SPs where f'(x)=0, so surely the derivitive graph=0 where there were SPs on the original graph... Doesn't it?

idk, now I'm doubting myself.
A is horizontal pt of inflexion, therefore at A, y' = 0 (reason why it touches x-axis) but values to the left and right of A will not change the sign of y' (we can see that y' > 0 for A < x and x> A). therefore the reason for a minimum at A

B is a pt of inflexion, meaning that y'' = 0 which means a maximum above the x - axis as y' > 0 for B < x and x > B.

lastly because there is a maximum at C, i'll cut the x-axis from above as y' > 0 for C < x and y' < 0 for x > C

therefore shape of derivative graph is \/\
 

hi im trash

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can anyone (if bothered) post the answers up for the MC ? i hope i got them right :/
i think theres a thread about MCQs already, could try looking there

what was the band 6 cut off for last year and the year before that? :S
 

Technoash

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can anyone (if bothered) post the answers up for the MC ? i hope i got them right :/
These are all from memory. Im not working any out again lol

1. A
2. B
3. D
4. C
5. B (i think)
6. D
7. B
8. A or D (the answer is B or C lol i fkd up)
9. A
10. A

Did I mess up anywhere?
 

chrisdelinet

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These are all from memory. Im not working any out again lol

1. A
2. B
3. D
4. C
5. B (i think)
6. D
7. B
8. A or D (the answer is B or C lol i fkd up)
9. A
10. A

Did I mess up anywhere?
i believe 8 is supposed to be C and 10 is D
 

nexusbrah

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These are all from memory. Im not working any out again lol

1. A
2. B
3. D
4. C
5. B (i think)
6. D
7. B
8. A or D (the answer is B or C lol i fkd up)
9. A
10. A

Did I mess up anywhere?
First one is B. 99% sure
 

WileyWanimal

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A is horizontal pt of inflexion, therefore at A, y' = 0 (reason why it touches x-axis) but values to the left and right of A will not change the sign of y' (we can see that y' > 0 for A < x and x> A). therefore the reason for a minimum at A

B is a pt of inflexion, meaning that y'' = 0 which means a maximum above the x - axis as y' > 0 for B < x and x > B.

lastly because there is a maximum at C, i'll cut the x-axis from above as y' > 0 for C < x and y' < 0 for x > C

therefore shape of derivative graph is \/\
;( :( Yes, you're right...
Would I get 2/3 because I had it right at B and C, and I at least knew it touched the axis at A?
 

phcan

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Omg same here i think i left like 20 marks worth of questions fml
 

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