Cambridge Prelim MX1 Textbook Marathon/Q&A (1 Viewer)

drsabz101

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

what about part b: I just got x=6,-3 but don't know what to do after?
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drsabz101

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

and part b) of this question:

2.PNG
 

leehuan

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

what about part b: I just got x=6,-3 but don't know what to do after?
View attachment 33240
You mean n is equal to 6 or -3.

Question: Can n possibly be negative?? Is there actually a thing called a negative term number?
 

leehuan

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

and part b) of this question:

View attachment 33241
3/32 * 2n = 10

2n = 320/3

This is a simple exponential equation that you should be able to solve using your knowledge of logs.

n ln(2) = ln(320/3)
n = ln(320/3)/ln(2)
n=6.73...

Therefore the first term number is n=7
 

drsabz101

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

no, but the answer is 5
 

drsabz101

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

ohh don't woryy
 

drsabz101

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

it's 5 because 6 is inclusive...
 

drsabz101

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

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InteGrand

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

We'd need to see Question 2) for this, but basically if they gave you a formula in terms of n for T_n, then you'd plot the graph as though it's a function but only at discrete points (e.g. n = 1,2,3,...).

If they only gave the first few terms of the sequence or a recursive formula, you'd plot the first few terms (the values on the vertical axis at n = 1,2,3,... on the horizontal axis), and you'd work out a formula for T_n in terms of n if needed.
 

drsabz101

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

okay , thankyou
 

drsabz101

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

how do you find the recursive formula?
 

drsabz101

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

Okay, Thanks I got the ans
 

drsabz101

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

for this q. I found part b. How can i se this for part c.?Capture.PNG
 

drsabz101

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

okay
 

drsabz101

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

how do do you parts b,c,d23.PNG
 

Drongoski

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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread

Do you know what Tn+1 means?



 
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