A function is defined as f(x) = x^2 - 3x + 4. What expression can be used to describe f(2x + 1)? Express your answer in simplified form in terms of x.
it is 2 - 4x
f(x) = x^2 - 3x + 4
f(2x+1) = (2x+1)^2 - 3(2x+1) + 4
now simplify