# Functions maths question

Hi, please could i have help on question 1? I don’t understand how i can find the inverse because i get x=6y^3-5y but how would i make y subject? Or is there an easier way to do this because it’s only 2 marks?
Here is the question: https://app.gemoo.com/share/image-annotation/614937557255499776?codeId=DWaq3oBYz1324&origin=imageurlgenerator

Thanks!
Why are you finding the inverse? You just need to differentiate it. f’(x) = 18x^2 - 5
f'(x)=df(x)/dx=18x2-5 ---> F''(x)= 36x F"(x=2)=............................................etc
Original post by lanky_giraffe
Why are you finding the inverse? You just need to differentiate it. f’(x) = 18x^2 - 5

Don't give answers - it's against forum rules
Original post by anonymous294
Hi, please could i have help on question 1? I don’t understand how i can find the inverse because i get x=6y^3-5y but how would i make y subject? Or is there an easier way to do this because it’s only 2 marks?
Here is the question: https://app.gemoo.com/share/image-annotation/614937557255499776?codeId=DWaq3oBYz1324&origin=imageurlgenerator

Thanks!

f'(x) menas differentiate wrt x.

f^-1 is the inverse function
Thank you! Sorry, I thought that was the inverse function ☹️
Original post by Muttley79
Don't give answers - it's against forum rules

My apologies