[M Kh]

(Original post by ak395)
Ok... thnx for that... i do like differentiation but i just looked at the book and all the weird symbols are scaring me but i guess ill take it as it goes... i have 93 average ums for my as level and i think *hope* i did well in m1 so i can afford to get slightly lower... ok i know u r probs not very interested but this is my form of calming myself down

Just try to achieve your best!!

[Souriretoujours]

(Original post by Eternal*)
Need an A x

Yu?

likewise its really beginning to stress me out especially after january's performance lol x

[otrivine]

my teacher thinks that this would be a hard paper ? and he said there could be a big question like differentiation/trig
when they c3 will be difficult like how cause all the papers seem to look same? which paper was the hardest till now?

[M Kh]

(Original post by otrivine)
my teacher thinks that this would be a hard paper ? and he said there could be a big question like differentiation/trig
when they c3 will be difficult like how cause all the papers seem to look same? which paper was the hardest till now?

Trigonometry and Differentiation are both very 'big' chapters so we must expect 'big' questions involving these two chapters.

[otrivine]

(Original post by M Kh)
Trigonometry and Differentiation are both very 'big' chapters so we must expect 'big' questions involving these two chapters.

but like which paper was the most difficult till now?

[Eternal*]

(Original post by Souriretoujours)


likewise its really beginning to stress me out especially after january's performance lol x

S2 didnt go too well either...
I need an average of 83UMS on S2 C3 C4

[Souriretoujours]

(Original post by Eternal*)


S2 didnt go too well either...
I need an average of 83UMS on S2 C3 C4

Yeah I repeated M1 in early may hoping to have got at least 70 UMS. S1 went really well so hoping for85-90 UMS which would leave me needing about 75 in C3 and C4 but I'm terrible at both of them so

[Callitoff]

I'm regretting resitting this paper, it's actually rather difficult in places... Hopefully a past paper a day will be enough.

[Eternal*]

(Original post by Souriretoujours)
Yeah I repeated M1 in early may hoping to have got at least 70 UMS. S1 went really well so hoping for85-90 UMS which would leave me needing about 75 in C3 and C4 but I'm terrible at both of them so

[0range]

I need around 68 in C3 and C4 to get an A but C3 atm is really starting to annoy me

[M Kh]

(Original post by otrivine)
but like which paper was the most difficult till now?

I am not sure really - it just depends on you. Maybe check the grade boundaries to see which was the hardest paper?

[-James-]

(Original post by M Kh)
I am not sure really - it just depends on you. Maybe check the grade boundaries to see which was the hardest paper?

jan 11 was quite hard imo...and jan 10.

[101101]

(Original post by grazie)
For part a), given that



Then



And the cosine of an angle is the same as the sin( - angle). So...



Taking arcsin on both sides



For part b), you're given arccos x in part a) and then worked out arcsin x. So




I think the problem with this question is that few (or perhaps none) examples are given in the textbook.

ah ok thank you

Yeah the problem was that i had never come across a problem like that before

[M Kh]

(Original post by -James-)
jan 11 was quite hard imo...and jan 10.

Yea, good luck revising.

[House3]

(Original post by emmaaa88)
I'm confused by this question in my textbook, I know it's just modulus but any help would be appreciated!

Sketch this graph:
y = |x+4| + |x-1|

Also does anyone have any useful ways of remembering the vector transformations because I am not good at those!

I have no idea how to sketch y = |x+4| + |x-1| tbh, that's mad hard.

But if you're asking about graph transformations (I assumed that's what you meant by vector transformations?), then I remember how to do graph transformations using this:

If y=f(x) and 'a' is a number, then perform the following actions to the graph:

y = af(x) -----> Multiply all y-coordinates by 'a'
y = f(x) + a -----> Add 'a' to all y-coordinates
y = f(ax) -----> Multiply all x-coordinates by '1/a'
y = f(x+a) -----> SUBTRACT 'a' from all x-coordinates.


Also, for me, I do graph transformations step-by-step and do the things closest to the 'x' first / using BIDMAS, so, if it gives you y = f(x) and says draw the graph of:

y = 2f(3x) - 5

I draw the graph of y=f(3x) first, by multiplying all x-coordinates by '1/3',

then I draw the graph of y = 2f(3x) by multiplying all y-coordinates by '2',

then I draw the final graph of y = 2f(3x) - 5 by subtracting '5' from all y-coordinates, which is the graph they're looking for.

Hope that helps a bit

[arnab]

anyone wanna explain the reasoning why this (the last part at the bottom) is wrong?



Uploaded with ImageShack.us

Sorry about the crappy quality of the image lol

[Dark Lord of Mordor]

(Original post by arnab)
anyone wanna explain the reasoning why this (the last part at the bottom) is wrong?



Uploaded with ImageShack.us

Sorry about the crappy quality of the image lol

When you apply a function to an equation, it must be applied to the whole of each individual side, as you would when dividing each side of an equation or multiplying each side of an equation. Hence you can't apply logarithms like that.

i.e. The second line should read ln(e^x + 3e^(-x)) = ln(4) which you can't do anything with.

You can solve this like so:

e^x + 3e^(-x) = 4

Multiply through by e^x

e^2x + 3 = 4e^x
e^2x - 4e^x + 3 = 0

Solve as you would a quadratic

(e^x - 1)(e^x - 3) = 0

e^x = 1, 3
x = ln(1), ln(3)
x = 0, 1.0986...

[-James-]

(Original post by M Kh)
Yea, good luck revising.

I thought compared to Jun 11 and Jan 12.

did you find them easy?

[StraightUpG]

any1 on here done the solomon papers for c3?

[James A]

Right, it's now time to get 90ums+ for my A*. Hopefully I can pull it off..