How do you find the critical numbers for g(t)=abs(3t-4) to determine the maximum and minimum?

1 Answer
Nov 4, 2016

See below.

Explanation:

g(t) = abs(3t-4) = { (3t-4,"if",t >= 4/3),(-3t+4,"if",t < 4/3 ) :}

g'(t) = { (3,"if",t >= 4/3),(-3,"if",t < 4/3 ) :}

g' is never 0 and is undefined (fals to exist) at x= 4/3

The only critical number is 4/3.

We see that g is decreasing left of 4/3 and increasing on the right.

So g(4/3) = 0 is a local minimum.