(a) Write down a corresponding definition for f(x) to converge to L as x→-00. Then, use the above definition and the definition you wrote to prove that 1 lim 1+00 1 + x² (b) Suppose f: R → R satisfies 1 = lim x-∞ 1 + x² = 0

Advanced Engineering Mathematics
10th Edition
ISBN:9780470458365
Author:Erwin Kreyszig
Publisher:Erwin Kreyszig
Chapter2: Second-order Linear Odes
Section: Chapter Questions
Problem 1RQ
icon
Related questions
Question

Please don't copy from Chegg. solution on Chegg is wrong

Let's take a look at limits of functions at infinity.
Given a function f : R → R and some LER, we say f(x) converges to L as x→ ∞ if
for all e > 0, there exists some MER such that for all x ≥ M,
I
|f(x) - L < €
In this case, we write f(x) → L as x → ∞, or
lim f(x):= L
x→∞
If f does not converge to any LER as x → ∞o, we say f diverges as x → ∞o.
(a) Write down a corresponding definition for f(x) to converge to L as x→ −x
Then, use the above definition and the definition you wrote to prove that
1
lim
1+00 1 + x²
(b) Suppose f: R → R satisfies
lim f(x) = lim f(x) = L
00+I
1
= lim
x-x 1 + x²
g(y): E
∞0-+*
for some LE R. Define a function g: R → R by
[f(1/y) y #0
L
y=0
Show that g is continuous at 0.
(Hint: For the - definition of continuity, show that you can break y < d into
three cases: y = 0, 1/y > 1/6, or -1/y > 1/6. This might help you find the right
value of 8.)
(c) Continuing from (b), show that if f is continuous at 0, then
lim g(y) = lim g(y) = f(0)
y-∞0
Transcribed Image Text:Let's take a look at limits of functions at infinity. Given a function f : R → R and some LER, we say f(x) converges to L as x→ ∞ if for all e > 0, there exists some MER such that for all x ≥ M, I |f(x) - L < € In this case, we write f(x) → L as x → ∞, or lim f(x):= L x→∞ If f does not converge to any LER as x → ∞o, we say f diverges as x → ∞o. (a) Write down a corresponding definition for f(x) to converge to L as x→ −x Then, use the above definition and the definition you wrote to prove that 1 lim 1+00 1 + x² (b) Suppose f: R → R satisfies lim f(x) = lim f(x) = L 00+I 1 = lim x-x 1 + x² g(y): E ∞0-+* for some LE R. Define a function g: R → R by [f(1/y) y #0 L y=0 Show that g is continuous at 0. (Hint: For the - definition of continuity, show that you can break y < d into three cases: y = 0, 1/y > 1/6, or -1/y > 1/6. This might help you find the right value of 8.) (c) Continuing from (b), show that if f is continuous at 0, then lim g(y) = lim g(y) = f(0) y-∞0
Expert Solution
steps

Step by step

Solved in 3 steps with 2 images

Blurred answer
Recommended textbooks for you
Advanced Engineering Mathematics
Advanced Engineering Mathematics
Advanced Math
ISBN:
9780470458365
Author:
Erwin Kreyszig
Publisher:
Wiley, John & Sons, Incorporated
Numerical Methods for Engineers
Numerical Methods for Engineers
Advanced Math
ISBN:
9780073397924
Author:
Steven C. Chapra Dr., Raymond P. Canale
Publisher:
McGraw-Hill Education
Introductory Mathematics for Engineering Applicat…
Introductory Mathematics for Engineering Applicat…
Advanced Math
ISBN:
9781118141809
Author:
Nathan Klingbeil
Publisher:
WILEY
Mathematics For Machine Technology
Mathematics For Machine Technology
Advanced Math
ISBN:
9781337798310
Author:
Peterson, John.
Publisher:
Cengage Learning,
Basic Technical Mathematics
Basic Technical Mathematics
Advanced Math
ISBN:
9780134437705
Author:
Washington
Publisher:
PEARSON
Topology
Topology
Advanced Math
ISBN:
9780134689517
Author:
Munkres, James R.
Publisher:
Pearson,