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Addmaths paper 1

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Yep and hence it will be hard :p

Not really. Trigonometry, Modulus Graphs and Linear Law are all just graph sketching and plotting. They're kinda like the 'free marks' of the paper.
If vectors for the unknowns 'lambda' and something come, it'll be easy peasy.
Circular Measure and Applications of Integration are easy too.
SOME Relative Velocity questions are hard, I hope the hard ones don't come.
 
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25/4 = nC2 (1/4) - nC1(1/2)
25/4 = n(n-1)(n-2)!/2!(n-2)! (1/4) - n(n-1)!/1!(n-1)! (1/2)
25/4 = n^2 - n/8 - n/2
50 = n^2 - n - 4n
n^2 - 5n - 50 = 0
Simplifying gives n=10 and n=-5 (rej.).

Please give the question for the trigonometry one, I'll solve.

well, its so surprising, u remember whole questions :p i find it so difficult to even remember my answers, but thank God, till now all answers are going perfect :)
 
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25/4 = nC2 (1/4) - nC1(1/2)
25/4 = n(n-1)(n-2)!/2!(n-2)! (1/4) - n(n-1)!/1!(n-1)! (1/2)
25/4 = n^2 - n/8 - n/2
50 = n^2 - n - 4n
n^2 - 5n - 50 = 0
Simplifying gives n=10 and n=-5 (rej.).

Please give the question for the trigonometry one, I'll solve.


Hey...
The equation was (1-sinQ-cosQ)^2 - 2(1-cosQ)(1-sinQ)
And mante, i wrote the range of k wrong.. i wrote less than 12 and 4...
And in the question we had to find P.. I found the gradiend wrong... like i wrote it 2... it was 1/2 and so got it all wrong...
How many marks will I lose...?
And oh! the binomial one... I put in the values but was confused so did not solve it furthur.. LOL
 
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Hey...
The equation was (1-sinQ-cosQ)^2 - 2(1-cosQ)(1-sinQ)
And mante, i wrote the range of k wrong.. i wrote less than 12 and 4...
And in the question we had to find P.. I found the gradiend wrong... like i wrote it 2... it was 1/2 and so got it all wrong...
How many marks will I lose...?
And oh! the binomial one... I put in the values but was confused so did not solve it furthur.. LOL

For the k, gradient and binomial, you'll only get partial credit for k and binomial. 1-2 marks for the gradient one.
Ok so, I let x = -sin Q - cos Q.
Then,
=(1+x)^2 - 2(1-cos Q)(1-sin Q)
=1 + 2x + x^2 - 2(1-sin Q - cos Q + sin Q cos Q).
=1 + 2(-sin Q - cos Q) + (-sin Q - cos Q)^2 - 2 + 2 sin Q + 2 cos Q - 2 sin Q cos Q
=1 - 2 sin Q -cos Q + sin^2 Q + 2 sin Q cos Q + cos^2 Q - 2 + 2 sin Q + 2 cos Q - 2 sin Q cos Q
Rearranging all the terms correctly,
=1-2 -2 sin Q + 2 sin Q - 2 cos Q + 2 cos Q + 2 sin Q cos Q - 2 sin Q cos Q + (sin^2 Q + cos^2 Q)
=-1 + (1)
=0
 
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For the k, gradient and binomial, you'll only get partial credit for k and binomial. 1-2 marks for the gradient one.
Ok so, I let x = -sin Q - cos Q.
Then,
=(1+x)^2 - 2(1-cos Q)(1-sin Q)
=1 + 2x + x^2 - 2(1-sin Q - cos Q + sin Q cos Q).
=1 + 2(-sin Q - cos Q) + (-sin Q - cos Q)^2 - 2 + 2 sin Q + 2 cos Q - 2 sin Q cos Q
=1 - 2 sin Q -cos Q + sin^2 Q + 2 sin Q cos Q + cos^2 Q - 2 + 2 sin Q + 2 cos Q - 2 sin Q cos Q
Rearranging all the terms correctly,
=1-2 -2 sin Q + 2 sin Q - 2 cos Q + 2 cos Q + 2 sin Q cos Q - 2 sin Q cos Q + (sin^2 Q + cos^2 Q)
=-1 + (1)
=0

Substitution ! Damn it ! Cudn't nail that one :(
 
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Substitution ! Damn it ! Cudn't nail that one :(

It could be done without substitution, you just had to deal with (-sin Q - cos Q) as one whole. I did not find it appropriate to follow working in this way so I substituted x.
 
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For the k, gradient and binomial, you'll only get partial credit for k and binomial. 1-2 marks for the gradient one.
Ok so, I let x = -sin Q - cos Q.
Then,
=(1+x)^2 - 2(1-cos Q)(1-sin Q)
=1 + 2x + x^2 - 2(1-sin Q - cos Q + sin Q cos Q).
=1 + 2(-sin Q - cos Q) + (-sin Q - cos Q)^2 - 2 + 2 sin Q + 2 cos Q - 2 sin Q cos Q
=1 - 2 sin Q -cos Q + sin^2 Q + 2 sin Q cos Q + cos^2 Q - 2 + 2 sin Q + 2 cos Q - 2 sin Q cos Q
Rearranging all the terms correctly,
=1-2 -2 sin Q + 2 sin Q - 2 cos Q + 2 cos Q + 2 sin Q cos Q - 2 sin Q cos Q + (sin^2 Q + cos^2 Q)
=-1 + (1)
=0


Would it get two or two would be cut...?
I wrote the gradient as 2 instead of 1/2 and then multiplying by 6 coz i was in a hurry lol...
And how much in The Binomial ques?
 
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