Sample Problems, Lesson 2.4
Sample Problems for this Lesson Course Home Page To the Notes Menu   Assignment  

2.4, #6, Given Problem.

Sketch the graph of a function that has a jump discontinuity at x = 2 and a removable discontinuity at x = 4, but is continuous elsewhere. 2.4, #6, Given Problem.
Here we have a graph which has the desired discontinuities.

Please note: There are an infinite number of graphs which could satisfy this set of requirements.


2.4, #26, Given Problem.

Use continuity to evaluate this limit:
2.4, #26, Given Problem.
is continuous for all 
We know that the sine function is continuous everywhere.
Because the function is everywhere continuous, the direct substitution method can be used.
We can now make this key substitution, and finish the problem.

2.4, #40. Given Problem.

Given that 
(a) Prove that the equation has at least one real root.
(b) Use your calculator to find an interval of length 0.01 that contains a root.
2.4, #40. Given Problem.
Part (a).

By Theorem 5 (p. 122) we know that polynomials are continuous everywhere. We know that at -1 the function is negative, and at 0 the function is positive. Add this to the fact that the function is continuous on this interval and the inevitable conclusion is that there must be a zero or root  in the interval [0,1]

A partial table of values shows that the root must be between -0.87 and -0.88.



Assignment
1-43, Odds
Lesson 2.4, Pages 128-130

To the Top of the PageTo the Course Home Page