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C2 June 2011 Edexcel - Paper and Solutions in the FIRST post.

there are a lot of questions on the pdf - possible c2 questions from papers P1 -P3 but are there any solutions anywhere?? thx

Reply 181

mchairmaster

I'm having a bit of trouble here to do with gradients: I understand that 2 perpendicular lines have a gradient product of -1, but (Specifically for Jan 09 C2 - Q5(a)) is there something special about a circle which makes 2 lines perpendicular(when there is a triangle within a circle)?

(edited 12 years ago)

Reply 182

gdunne42

21

Original post by mchairmaster

I'm having a bit of trouble here to do with gradients: I have it guessed that when 2 gradients are multiplied they become -1, but i have never learnt this and don't know with what conditions and really what its referring to. Could anyone tell me what this rule's name is or explain the concept of it? edit: - I understand also that 2 perpendicular lines have a gradient product of -1, but (Specifically for Jan 09 C2 - Q5(a)) is there something special about a circle which makes 2 lines perpendicular?

Revise the circle theorems from GCSE
One of them tells you that the angle in a semicrcle is always a right angle.
Another tells you that a tangent to a circle forms a right angle with the radius
In either of these circumstances you have lines that are perpendicular to each other and the product of their gradients = -1

Reply 183

gdunne42

21

Original post by murdeb

there are a lot of questions on the pdf - possible c2 questions from papers P1 -P3 but are there any solutions anywhere?? thx

There are marks schemes for most of the P1-P3 papers at freeexampapers.com

Reply 184

Legendary

1

Time to make that 83 ums into a 100 ums. :colone:

Reply 185

Arsey

OP

10

Original post by Cleoleo

Ah help please! Q8c, Jan 2010, could someone explain how they know that the line 12cm can be halved exactly into 6 and 6 at the point N?

check out the model answers, available in the first few posts of this thread.

Reply 186

Moody

Does anyone know how to use the 'Box' method, as Arsey claimed it was easier :smile:

?

Reply 187

therapist_1

Original post by sannah123

Do you mean Q9b?
If you do, to work out the area when y>0, do equation of line minus equation of curve and intergrate that between the x values

Yea i understand that. Just wanted to kno why when we intergrate we dont include the +c at the end?? :confused:

Reply 188

gdunne42

21

Original post by therapist_1

Yea i understand that. Just wanted to kno why when we intergrate we dont include the +c at the end?? :confused:

for definite integration between limits let's say between x=1 and x=2

and for example the integral of your given function = x^2 + c

between 1 and 2 this gives Area = (2^2 + c) - (1^2 + c)

the +c's cancel out, they always do

(edited 12 years ago)

Reply 189

intellectual1

3

Original post by gdunne42

There are marks schemes for most of the P1-P3 papers at freeexampapers.com

Google properly and you'll be suprised! :rolleyes:

Reply 190

lady-nana

i need help regarding radians .. anybody has an idea ? :/
im thankful

Reply 191

intellectual1

3

Original post by Moody

Does anyone know how to use the 'Box' method, as Arsey claimed it was easier :smile:

?

Please search the earlier posts of this thread...alot of useful tips are within this thread. There is an attachement of it in a post earlier on...

Reply 192

intellectual1

3

Original post by lady-nana

i need help regarding radians .. anybody has an idea ? :/
im thankful

Radian mode on your calculator...not degrees!

the magic number is 180! :wink:

Reply 193

The Polar Dude

Hiya guys
when you have a sin graph in radians and they tell you to shift it to the left by 30, how do you get the new co-ordinates?
i know you do pi minus the 30 but how do you get 30 into radians. is this simple or am i being daft? help

Reply 194

Arsey

OP

10

Original post by Moody

Does anyone know how to use the 'Box' method, as Arsey claimed it was easier :smile:

?

learn it, thank me later.

I posted some instructions on the first page (I think)

http://www.thestudentroom.co.uk/showpost.php?p=31304124&postcount=25

(edited 12 years ago)

Reply 195

Arsey

OP

10

Original post by The Polar Dude

Hiya guys
when you have a sin graph in radians and they tell you to shift it to the left by 30, how do you get the new co-ordinates?
i know you do pi minus the 30 but how do you get 30 into radians. is this simple or am i being daft? help

pi radians is 180 degrees

1/2 pi = 90

1/4 pi = 45

1/6 pi = 30

every angle in degrees is a fraction of pi radians

very simple method to convert degrees into radians

write pi after the angle in degrees and then put 180 underneath (simplify if necessary, or smack in the calc for a decimal answer)

30 degrees =

\frac{30\pi}{180}

radians

If you find radians difficult, just do everything in degrees but convert your final answer to zero.

(edited 12 years ago)

Reply 196

The Polar Dude

Original post by Arsey

pi radians is 180 degrees

1/2 pi = 90

1/4 pi = 45

1/6 pi = 30

every angle in degrees is a fraction of pi radians

very simple method to convert degrees into radians

write pi after the angle in degrees and then put 180 underneath (simplify if necessary, or smack in the calc for a decimal answer)

30 degrees =

\frac{30\pi}{180}

radians

If you find radians difficult, just do everything in degrees but convert your final answer to zero.

thank you very much :biggrin:

and one more thing
in the series and sequences, my C2 book is confusing me with this new method

Q: An investor invests £2000 on January 1st every year in a savings account that guarantees him 4% per annum for life. If interest is calculated on the 31st of December each year, how much will be in the account at the end of the 10th year?

basically, i was gonna do ar^9 so a is 2000, r is 1.04 but the book does something else and got an answer is £24972.20

Reply 197

NaTuRe_LoViN

LIFE saver!!! will you marry me?

Reply 198

megan.

1

Original post by The Polar Dude

thank you very much :biggrin:

and one more thing
in the series and sequences, my C2 book is confusing me with this new method

Q: An investor invests £2000 on January 1st every year in a savings account that guarantees him 4% per annum for life. If interest is calculated on the 31st of December each year, how much will be in the account at the end of the 10th year?

basically, i was gonna do ar^9 so a is 2000, r is 1.04 but the book does something else and got an answer is £24972.20