SO what you need to do is: <span>Start with |f(x) - 3| < 0.4 and plug in f(x) = x+1 to get
|f(x) – 3| < 0.4
|x+1 – 3| < 0.4 |x - 2| < 0.4 -0.4 < x - 2 < 0.4
-0.4+2 < x < 0.4+2
1.6 < x < 2.4 So delta would be 2.3 Hope this is what you were looking for </span>
