Cambridge Prelim MX1 Textbook Marathon/Q&A (1 Viewer)
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leehuan
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Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread
Question: Can n possibly be negative?? Is there actually a thing called a negative term number?
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
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
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
Re: Year 11 Mathematics 3 Unit Cambridge Question & Answer Thread
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.
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
Don't need to. Just combine the fractions in the given expression for T_n at the start of the Q.
