jamesfirst
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Can I get 1 mark if I did it wrong ?
A decent 2 unit student could do it.You actually do turning points in 3 unit. lol Is it possible for a 2 unit student to do? or is the question much harder than a 2 unit version? what was the question?
Yes, there are a few additions to trigonometry differentiation though.You actually do turning points in 3 unit. lol Is it possible for a 2 unit student to do? or is the question much harder than a 2 unit version? what was the question?
Oh wow, what question would it be in? Q1 -7. I think I've done a similar question to this in past papers.A decent 2 unit student could do it.
f(x) = e^-x - 2e^-2x
Had to find f '(x), the max turning point, the x and y intercepts, what the graph did as x approached infinity, and then graph it.
That was for 8 marks. Pretty generous question 4.
I don't know how but I got the y-intercept as the turning point...A decent 2 unit student could do it.
f(x) = e^-x - 2e^-2x
Had to find f '(x), the max turning point, the x and y intercepts, what the graph did as x approached infinity, and then graph it.
That was for 8 marks. Pretty generous question 4.
ahaha it happens. It's best to set out your work neatly for these questions and don't rush. Because a simple early error can lead to a fatal answer and you will have to do the whole question again to get the right points etc.I don't know how but I got the y-intercept as the turning point...
maybe I used f(x)............ god DAMNIT
Yeah I mixed them up on the graph. :/dude. I put maximum as the y intercept and I was like... wtffffffffffffffff
Was the maximum turning point at like (-1.2x, -28) ? Because the y intercept was all the way at the top? And i was like "this doesnt look right"
I think the turning point was (ln4, 1/8)Was the maximum turning point at like (-1.2x, -28) ? Because the y intercept was all the way at the top? And i was like "this doesnt look right"
I assume that you'd usually have to. f'(x)=0 does not automatically mean it's a max. point. It could be a minimum or a horizontal point of inflexion or whatever for all you know.do you have to show that it's a max? :|
You dont have to show its a max because the question says its a max alreadyI think the turning point was (ln4, 1/8)
The y intercept was -1.
I assume that you'd usually have to. f'(x)=0 does not automatically mean it's a max. point. It could be a minimum or a horizontal point of inflexion or whatever for all you know.
Ah, okay I couldn't remember what the question said and I cbf to look it up. I stand corrected.You dont have to show its a max because the question says its a max already
haha no worries =)Ah, okay I couldn't remember what the question said and I cbf to look it up. I stand corrected.
I was taught to show it even though it says maximum. Either that or it must be a habit.You dont have to show its a max because the question says its a max already
Same here, i was taught to show it regardless the mark allocated to that questionI was taught to show it even though it says maximum. Either that or it must be a habit.
mmm yeah thats what our teachers tell us but id be surprised if they took marks off cos the question says "f(x) has one maximum turning point, find the coordinates of the turning point" and when you solve f'(x) you only get one possible x value that solves f'(x) = 0 so it would be fair to assume that it is the maximum turning point the question is referring tooSame here, i was taught to show it regardless the mark allocated to that question