Help me how to proceed (Area of a Surface of Revolution)

[clear wharf]

this is what I have so far, not sure if it's right

also I can't decide whether to convert 1/x^4 into some type of ln|x| or do u sub

Textbook answer:

now looking at this, I wonder if 1/x^4 becomes 4ln|x|, this moves the power of x to the front

[solid glade]

youre not going to believe this but youll need to u-sub u = √(1 + 1/x^4)

remember that you can always force a u-sub by using the equation u = √(1 + 1/x^4) to solve for x
this will get you "x = something" which you can use to replace every x with a correct expression in u

[clear wharf]

Oh my god I have to u sub it with the square root too? Why didn't I think of that?