The sign-preserving property of continuous functions Let f be defined on an interval (a, b) and suppose that f(c) ≠ 0 at some c where f is continuous. Show that there is an interval (c − δ, c + δ) about c where f has the same sign as f(c).
1. Limits and Continuity
Continuity
- Textbook Question
- Textbook Question
Use the Intermediate Value Theorem in Exercises 69–74 to prove that each equation has a solution. Then use a graphing calculator or computer grapher to solve the equations.
x³ − 3x − 1 = 0
- Textbook Question
Use the Intermediate Value Theorem in Exercises 69–74 to prove that each equation has a solution. Then use a graphing calculator or computer grapher to solve the equations.
x³ − 15x + 1 = 0 (three roots)
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At what points are the functions in Exercises 13–30 continuous?
y = cos (x) / x
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At what points are the functions in Exercises 13–30 continuous?
y = √(2x + 3)
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At what points are the functions in Exercises 13–30 continuous?
g(x) = { (x² − x – 6)/(x – 3), x ≠ 3
5, x = 3
- Textbook Question
Is there a value of c that will make
f(x) = { (sin²(3x)) / x², x ≠ 0
c, x = 0
continuous at x = 0? Give reasons for your answer.
- Textbook Question
Limits and Continuity
Graph the function
1 , x ≤ ―1
―x , ―1 < x < 0
ƒ(x) = { 1 , x = 0 ,
―x , 0 < x < 1
1 , x ≥ 1
Then discuss, in detail, limits, one-sided limits, continuity, and one-sided continuity of ƒ at x = ―1 , 0 , and 1. Are any of the discontinuities removable? Explain.