# proofs for edexcel mathsWatch

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#1
hi guys, can someone tell me the proofs we need to know for c1, c2 and s1, c3, c4 and s2?

thank you ;D
1
2 years ago
#2
(Original post by tangent33)
hi guys, can someone tell me the proofs we need to know for c1, c2 and s1, c3, c4 and s2?

thank you ;D
Sum of an arithmetic series formula
Sum of a geometric series formula
sec/tan and cosec/cot identities.
Double angle formulas (using addition formulae)
Derivative of .
Integrals of tan/cot (on formula book but simple proofs)

2
2 years ago
#3
(Original post by tangent33)
anybody?
You should post maths questions in the maths forum if you want faster replies (I've just moved this one for you). And please don't bump your threads - you're much more likely to get a response if you leave your thread unanswered.
0
2 years ago
#4
(Original post by tangent33)
hi guys, can someone tell me the proofs we need to know for c1, c2 and s1, c3, c4 and s2?

thank you ;D
For S1 I don't remember anything.

For S2 I believe you need to be able to find E(X) and Var(X) for a given distribution, including standard ones like for continuous uniform and all that although not the variance for that one.
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2 years ago
#5
I think also the sine and cosine rules and I'm not too sure about the quadratic equation one.
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2 years ago
#6
(Original post by Miss.Modesty)
I think also the sine and cosine rules and I'm not too sure about the quadratic equation one.
No proofs of the sine/cosine rules and quadratic formula are not required for A Level.
0
2 years ago
#7
Proof of the sum of odd and even numbers, the product of odd and even numbers is ... number.
Direct proof.
Proof by inspection (work every possibility out).
The equating of two trig with a three lined equal sign between them is a type of proof too.
The proof for the statistics is just deriving the formulas and you should know them because they explain how you get them.
The reasons for F(x) = 1
Deriving the formula for events
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2 years ago
#8
(Original post by Anfanny)
Proof by inspection (work every possibility out).
The equating of two trig with a three lined equal sign between them is a type of proof too.
The reasons for F(x) = 1
• This is called proof by exhaustion/brute force
• Proving trigonometric identities, you mean?
• What do you mean? What is ?
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2 years ago
#9
(Original post by _gcx)
• This is called proof by exhaustion/brute force
• Proving trigonometric identities, you mean?
• What do you mean? What is ?
I was going to write brute force!
Trig identities proof yes but there can also be anything they ask you so get from point A to point B. Well you need to understand that because that's all there can be.
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2 years ago
#10
(Original post by Anfanny)
I was going to write brute force!
Trig identities proof yes but there can also be anything they ask you so get from point A to point B. Well you need to understand that because that's all there can be.
I recommend you post a specific example since is very confusing and it's hard to know what you're trying to say,
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2 years ago
#11
(Original post by notnek)
I recommend you post a specific example since is very confusing and it's hard to know what you're trying to say,
The sum of all the probabilities in a given set where the amount of events does not change is equal to one. This can include the probability that the events do not happen which is an event on its own.

So

0
2 years ago
#12
(Original post by Anfanny)
The sum of all the probabilities in a given set where the amount of events does not change is equal to one. This can include the probability that the events do not happen which is an event on its own.

So

Ah you're talking about probability - you really should have mentioned this since "The reasons for F(x) = 1" could have meant anything
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2 years ago
#13
(Original post by notnek)
Ah you're talking about probability - you really should have mentioned this since "The reasons for F(x) = 1" could have meant anything
It's a Capitol F and Edexcel so it only means one thing. Please stop posting unhelpful comments.
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2 years ago
#14
(Original post by _gcx)
No, it does not mean only one thing. (for example, it can be an antiderivative, one of a few functions like the Dawson function, etc.) There is more to mathematics than examinations (I've seen you apply the attitude that "the exam board or 'my textbook' says this, so it's true"
(Original post by tangent33)
hi guys, can someone tell me the proofs we need to know for c1, c2 and s1, c3, c4 and s2?

thank you ;D
Not here, you haven't been reading the original post.
0
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