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# finding f'(x) help watch

1. Hi,
How to find f'(x) when f(x)=x + 3/x ?
4 marks worth exam question.
Thank you!
2. (Original post by Ieva Radskaite)
Hi,
How to find f'(x) when f(x)=x + 3/x ?
4 marks worth exam question.
Thank you!
Write x as x^-1 so, 3x^-1
then you'll be able to differentiate it easily
3. (Original post by Mary562)
Write x as x^-1 so, 3x^-1
then you'll be able to differentiate it easily
Thank you!
4. (Original post by Ieva Radskaite)
Thank you!
Welcome

What answer have you got ?
5. (Original post by Mary562)
Welcome

What answer have you got ?
f'(x) = 1 - 3x^-2
Right?
6. (Original post by Ieva Radskaite)
f'(x) = 1 - 3x^-2
Right?
Yep well done
7. (Original post by Mary562)
Yep well done
8. (Original post by Ieva Radskaite)
You're welcome

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