Integration, please help!

Question

Which of the following integrals cannot be evaluated using a simple substitution?

Options:

1. 
2. 
3. 
4. 

Answer 1

# 1 let u = x-1

# 2 is just the arcsin(x) which does not use any substitution.

# 3 let u = 1-x^2

# 4 let x = sec(u)