Further Maths GCSE AQA

Hey, I'm stuck on the following question. I understand how to differentiate but when I get to -4/x I can't seem to understand how to differentiate this. Is it something to do with index laws?

Question:
Work out dy/dx for y= 1/4 (x^4 +2x -4)

(edited 1 year ago)

Reply 1

Notnek

21

Original post by convivialkiwi

Hey, I'm stuck on the following question. I understand how to differentiate but when I get to -4/x I can't seem to understand how to differentiate this. Is it something to do with index laws?

Question:
Work out dy/dx for y= 1/4 (x^4 +2x -4)

Is that

\displaystyle \frac{1}{4}\left(x^4+2x-4\right)

Or did you make a typo?

If it is then can you explain where -4/x came from?

Reply 2

davros

16

Original post by convivialkiwi

Hey, I'm stuck on the following question. I understand how to differentiate but when I get to -4/x I can't seem to understand how to differentiate this. Is it something to do with index laws?

Question:
Work out dy/dx for y= 1/4 (x^4 +2x -4)

There isn't a "-4/x" in that expression for y! Can you upload a picture of the original question?

Reply 3

ollie5647

6

pretty sure u just simplify first (0.25x+0.5x-1) then differentiate

Original post by convivialkiwi

Hey, I'm stuck on the following question. I understand how to differentiate but when I get to -4/x I can't seem to understand how to differentiate this. Is it something to do with index laws?

Question:
Work out dy/dx for y= 1/4 (x^4 +2x -4)

Reply 4

BENgal232

4

Original post by convivialkiwi

Hey, I'm stuck on the following question. I understand how to differentiate but when I get to -4/x I can't seem to understand how to differentiate this. Is it something to do with index laws?

Question:
Work out dy/dx for y= 1/4 (x^4 +2x -4)