Can someone check my work on these please? 1. find a point c satisfying mean value theorem for f(x) = 1/x on [1,4]

shouldn't this be c = -4 ?

2. determine the intervals for which the function f(x) = x^2 + 8ln(x) - 10x is increasing

shouldn't this be on (-infinity, 1) U (4, infinity) ?

3. see the attached picture

shouldn't this be (-infinity, -2) U (1, infinity) ?