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A-Level Maths Functions

Can anyone help explain what this question means and how to do the first couple so I know what I'm meant to do?
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Reply 1
Original post by Meggggggggggg
Can anyone help explain what this question means and how to do the first couple so I know what I'm meant to do?
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Chain two or more functions together so the output of one is the input to another.

For the second one, which functions might be useful?
Original post by mqb2766
Chain two or more functions together so the output of one is the input to another.

For the second one, which functions might be useful?

oh ok, so for example jg(x) would be 4sqrtx? How would you then divide it by 2 to get part ii)?
Reply 3
Original post by Meggggggggggg
oh ok, so for example jg(x) would be 4sqrtx? How would you then divide it by 2 to get part ii)?

Close with jg(x), but think about the order. How can a 4 become 2? Not just by dividing by 2.
Original post by mqb2766
Close with jg(x), but think about the order. How can a 4 become 2? Not just by dividing by 2.

gj(x)? would that then be sqrt4x which is the same as sqrt4sqrtx which is 2sqrtx??
Reply 5
Original post by Meggggggggggg
gj(x)? would that then be sqrt4x which is the same as sqrt4sqrtx which is 2sqrtx??

Yes. That's the sort of thinking about elementary functions and how they're chained together they want you to do.
Original post by mqb2766
Yes. That's the sort of thinking about elementary functions and how they're chained together they want you to do.

ok thanks! however i'm still confused about part iii), when there's indices involved i get confused.
Reply 7
Original post by Meggggggggggg
ok thanks! however i'm still confused about part iii), when there's indices involved i get confused.

So what does a +1 in the index represent. Which elementary functions may be useful?

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