Calculus: Early Transcendentals (2nd Edition)
2nd Edition
ISBN: 9780321947345
Author: William L. Briggs, Lyle Cochran, Bernard Gillett
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Question
Chapter 9.1, Problem 4E
To determine
To find: The common terms of the Taylor polynomials
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionChapter 9 Solutions
Calculus: Early Transcendentals (2nd Edition)
Ch. 9.1 - Suppose you use a second-order Taylor polynomial...Ch. 9.1 - Does the accuracy of an approximation given by a...Ch. 9.1 - The first three Taylor polynomials for f(x)=1+x...Ch. 9.1 - Prob. 4ECh. 9.1 - How is the remainder Rn(x) in a Taylor polynomial...Ch. 9.1 - Explain how to estimate the remainder in an...Ch. 9.1 - Linear and quadratic approximation a. Find the...Ch. 9.1 - Linear and quadratic approximation a. Find the...Ch. 9.1 - Linear and quadratic approximation a. Find the...Ch. 9.1 - Linear and quadratic approximation a. Find the...
Ch. 9.1 - Linear and quadratic approximation a. Find the...Ch. 9.1 - Linear and quadratic approximation a. Find the...Ch. 9.1 - Linear and quadratic approximation a. Find the...Ch. 9.1 - Linear and quadratic approximation a. Find the...Ch. 9.1 - Taylor polynomials a. Find the nth-order Taylor...Ch. 9.1 - Taylor polynomials a. Find the nth-order Taylor...Ch. 9.1 - Taylor polynomials a. Find the nth-order Taylor...Ch. 9.1 - Prob. 18ECh. 9.1 - Prob. 19ECh. 9.1 - Prob. 20ECh. 9.1 - Prob. 21ECh. 9.1 - Prob. 22ECh. 9.1 - Approximations with Taylor polynomials a. Use the...Ch. 9.1 - Prob. 24ECh. 9.1 - Prob. 25ECh. 9.1 - Approximations with Taylor polynomials a. Use the...Ch. 9.1 - Approximations with Taylor polynomials a. Use the...Ch. 9.1 - Prob. 28ECh. 9.1 - Taylor polynomials centered at a 0 a. Find the...Ch. 9.1 - Taylor polynomials centered at a 0 a. Find the...Ch. 9.1 - Prob. 31ECh. 9.1 - Prob. 32ECh. 9.1 - Prob. 33ECh. 9.1 - Prob. 34ECh. 9.1 - Prob. 35ECh. 9.1 - Prob. 36ECh. 9.1 - Prob. 37ECh. 9.1 - Prob. 38ECh. 9.1 - Approximations with Taylor polynomials a....Ch. 9.1 - Approximations with Taylor polynomials a....Ch. 9.1 - Approximations with Taylor polynomials a....Ch. 9.1 - Approximations with Taylor polynomials a....Ch. 9.1 - Approximations with Taylor polynomials a....Ch. 9.1 - Approximations with Taylor polynomials a....Ch. 9.1 - Prob. 45ECh. 9.1 - Approximations with Taylor polynomials a....Ch. 9.1 - Approximations with Taylor polynomials a....Ch. 9.1 - Prob. 48ECh. 9.1 - Remainders Find the remainder Rn for the nth-order...Ch. 9.1 - Remainders Find the remainder Rn for the nth-order...Ch. 9.1 - Prob. 51ECh. 9.1 - Remainders Find the remainder Rn for the nth-order...Ch. 9.1 - Remainders Find the remainder Rn for the nth-order...Ch. 9.1 - Remainders Find the remainder Rn for the nth-order...Ch. 9.1 - Estimating errors Use the remainder to find a...Ch. 9.1 - Estimating errors Use the remainder to find a...Ch. 9.1 - Estimating errors Use the remainder to find a...Ch. 9.1 - Estimating errors Use the remainder to find a...Ch. 9.1 - Estimating errors Use the remainder to find a...Ch. 9.1 - Estimating errors Use the remainder to find a...Ch. 9.1 - Error bounds Use the remainder to find a bound on...Ch. 9.1 - Prob. 62ECh. 9.1 - Error bounds Use the remainder to find a bound on...Ch. 9.1 - Error bounds Use the remainder to find a bound on...Ch. 9.1 - Error bounds Use the remainder to find a bound on...Ch. 9.1 - Error bounds Use the remainder to find a bound on...Ch. 9.1 - Number of terms What is the minimum order of the...Ch. 9.1 - Number of terms What is the minimum order of the...Ch. 9.1 - Number of terms What is the minimum order of the...Ch. 9.1 - Number of terms What is the minimum order of the...Ch. 9.1 - Number of terms What is the minimum order of the...Ch. 9.1 - Number of terms What is the minimum order of the...Ch. 9.1 - Explain why or why not Determine whether the...Ch. 9.1 - Prob. 74ECh. 9.1 - Matching functions with polynomials Match...Ch. 9.1 - Prob. 76ECh. 9.1 - Small argument approximations Consider the...Ch. 9.1 - Prob. 78ECh. 9.1 - Prob. 79ECh. 9.1 - Prob. 80ECh. 9.1 - Small argument approximations Consider the...Ch. 9.1 - Small argument approximations Consider the...Ch. 9.1 - Small argument approximations Consider the...Ch. 9.1 - Prob. 84ECh. 9.1 - Prob. 85ECh. 9.1 - Prob. 86ECh. 9.1 - Prob. 87ECh. 9.1 - Prob. 88ECh. 9.1 - Prob. 89ECh. 9.1 - Prob. 90ECh. 9.1 - Best expansion point Suppose you wish to...Ch. 9.1 - Prob. 92ECh. 9.1 - Tangent line is p1 Let f be differentiable at x =...Ch. 9.1 - Local extreme points and inflection points Suppose...Ch. 9.1 - Prob. 95ECh. 9.1 - Approximating In x Let f(x) = ln x and let pn and...Ch. 9.1 - Approximating square roots Let p1 and q1 be the...Ch. 9.1 - A different kind of approximation When...Ch. 9.2 - Write the first four terms of a power series with...Ch. 9.2 - Prob. 2ECh. 9.2 - What tests are used to determine the radius of...Ch. 9.2 - Prob. 4ECh. 9.2 - Do the interval and radius of convergence of a...Ch. 9.2 - Prob. 6ECh. 9.2 - Prob. 7ECh. 9.2 - Prob. 8ECh. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Prob. 10ECh. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Prob. 26ECh. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Interval and radius of convergence Determine the...Ch. 9.2 - Combining power series Use the geometric series...Ch. 9.2 - Combining power series Use the geometric series...Ch. 9.2 - Combining power series Use the geometric series...Ch. 9.2 - Combining power series Use the geometric series...Ch. 9.2 - Combining power series Use the geometric series...Ch. 9.2 - Combining power series Use the geometric series...Ch. 9.2 - Combining power series Use the power series...Ch. 9.2 - Combining power series Use the power series...Ch. 9.2 - Prob. 37ECh. 9.2 - Combining power series Use the power series...Ch. 9.2 - Combining power series Use the power series...Ch. 9.2 - Prob. 40ECh. 9.2 - Differentiating and integrating power series Find...Ch. 9.2 - Differentiating and integrating power series Find...Ch. 9.2 - Differentiating and integrating power series Find...Ch. 9.2 - Differentiating and integrating power series Find...Ch. 9.2 - Differentiating and integrating power series Find...Ch. 9.2 - Differentiating and integrating power series Find...Ch. 9.2 - Prob. 47ECh. 9.2 - Functions to power series Find power series...Ch. 9.2 - Functions to power series Find power series...Ch. 9.2 - Functions to power series Find power series...Ch. 9.2 - Functions to power series Find power series...Ch. 9.2 - Functions to power series Find power series...Ch. 9.2 - Explain why or why not Determine whether the...Ch. 9.2 - Radius of convergence Find the radius of...Ch. 9.2 - Radius of convergence Find the radius of...Ch. 9.2 - Summation notation Write the following power...Ch. 9.2 - Summation notation Write the following power...Ch. 9.2 - Prob. 58ECh. 9.2 - Prob. 59ECh. 9.2 - Scaling power series If the power series...Ch. 9.2 - Shifting power series If the power series...Ch. 9.2 - Prob. 62ECh. 9.2 - Series to functions Find the function represented...Ch. 9.2 - Series to functions Find the function represented...Ch. 9.2 - Prob. 65ECh. 9.2 - Series to functions Find the function represented...Ch. 9.2 - Series to functions Find the function represented...Ch. 9.2 - A useful substitution Replace x with x 1 in the...Ch. 9.2 - Prob. 69ECh. 9.2 - Prob. 70ECh. 9.2 - Prob. 71ECh. 9.2 - Exponential function In Section 9.3, we show that...Ch. 9.2 - Prob. 73ECh. 9.2 - Remainders Let f(x)=k=0xk=11xandSn(x)=k=0n1xk. The...Ch. 9.2 - Prob. 75ECh. 9.2 - Inverse sine Given the power series...Ch. 9.2 - Prob. 77ECh. 9.3 - How are the Taylor polynomials for a function f...Ch. 9.3 - What conditions must be satisfied by a function f...Ch. 9.3 - Prob. 3ECh. 9.3 - Prob. 4ECh. 9.3 - Prob. 5ECh. 9.3 - For what values of p does the Taylor series for...Ch. 9.3 - In terms of the remainder, what does it mean for a...Ch. 9.3 - Prob. 8ECh. 9.3 - Maclaurin series a. Find the first four nonzero...Ch. 9.3 - Maclaurin series a. Find the first four nonzero...Ch. 9.3 - Maclaurin series a. Find the first four nonzero...Ch. 9.3 - Maclaurin series a. Find the first four nonzero...Ch. 9.3 - Maclaurin series a. Find the first four nonzero...Ch. 9.3 - Prob. 14ECh. 9.3 - Maclaurin series a. Find the first four nonzero...Ch. 9.3 - Maclaurin series a. Find the first four nonzero...Ch. 9.3 - Maclaurin series a. Find the first four nonzero...Ch. 9.3 - Maclaurin series a. Find the first four nonzero...Ch. 9.3 - Prob. 19ECh. 9.3 - Maclaurin series a. Find the first four nonzero...Ch. 9.3 - Taylor series centered at a 0 a. Find the first...Ch. 9.3 - Taylor series centered at a 0 a. Find the first...Ch. 9.3 - Taylor series centered at a 0 a. Find the first...Ch. 9.3 - Taylor series centered at a 0 a. Find the first...Ch. 9.3 - Taylor series centered at a 0 a. Find the first...Ch. 9.3 - Taylor series centered at a 0 a. Find the first...Ch. 9.3 - Taylor series centered at a 0 a. Find the first...Ch. 9.3 - Prob. 28ECh. 9.3 - Prob. 29ECh. 9.3 - Prob. 30ECh. 9.3 - Prob. 31ECh. 9.3 - Prob. 32ECh. 9.3 - Prob. 33ECh. 9.3 - Prob. 34ECh. 9.3 - Prob. 35ECh. 9.3 - Prob. 36ECh. 9.3 - Prob. 37ECh. 9.3 - Prob. 38ECh. 9.3 - Binomial series a. Find the first four nonzero...Ch. 9.3 - Binomial series a. Find the first four nonzero...Ch. 9.3 - Prob. 41ECh. 9.3 - Binomial series a. Find the first four nonzero...Ch. 9.3 - Binomial series a. Find the first four nonzero...Ch. 9.3 - Binomial series a. Find the first four nonzero...Ch. 9.3 - Prob. 45ECh. 9.3 - Prob. 46ECh. 9.3 - Prob. 47ECh. 9.3 - Working with binomial series Use properties of...Ch. 9.3 - Prob. 49ECh. 9.3 - Working with binomial series Use properties of...Ch. 9.3 - Working with binomial series Use properties of...Ch. 9.3 - Working with binomial series Use properties of...Ch. 9.3 - Working with binomial series Use properties of...Ch. 9.3 - Working with binomial series Use properties of...Ch. 9.3 - Working with binomial series Use properties of...Ch. 9.3 - Working with binomial series Use properties of...Ch. 9.3 - Remainders Find the remainder in the Taylor series...Ch. 9.3 - Prob. 58ECh. 9.3 - Remainders Find the remainder in the Taylor series...Ch. 9.3 - Remainders Find the remainder in the Taylor series...Ch. 9.3 - Explain why or why not Determine whether the...Ch. 9.3 - Any method a. Use any analytical method to find...Ch. 9.3 - Any method a. Use any analytical method to find...Ch. 9.3 - Any method a. Use any analytical method to find...Ch. 9.3 - Any method a. Use any analytical method to find...Ch. 9.3 - Any method a. Use any analytical method to find...Ch. 9.3 - Any method a. Use any analytical method to find...Ch. 9.3 - Any method a. Use any analytical method to find...Ch. 9.3 - Any method a. Use any analytical method to find...Ch. 9.3 - Approximating powers Compute the coefficients for...Ch. 9.3 - Approximating powers Compute the coefficients for...Ch. 9.3 - Approximating powers Compute the coefficients for...Ch. 9.3 - Prob. 73ECh. 9.3 - Prob. 74ECh. 9.3 - Integer coefficients Show that the first five...Ch. 9.3 - Choosing a good center Suppose you want to...Ch. 9.3 - Alternative means By comparing the first four...Ch. 9.3 - Alternative means By comparing the first four...Ch. 9.3 - Prob. 79ECh. 9.3 - Prob. 80ECh. 9.3 - Prob. 81ECh. 9.3 - Composition of series Use composition of series to...Ch. 9.3 - Prob. 83ECh. 9.3 - Approximations Choose a Taylor series and center...Ch. 9.3 - Approximations Choose a Taylor series and center...Ch. 9.3 - Prob. 86ECh. 9.3 - Prob. 87ECh. 9.3 - Prob. 88ECh. 9.3 - Prob. 89ECh. 9.3 - Prob. 90ECh. 9.4 - Explain the strategy presented in this section for...Ch. 9.4 - Explain the method presented in this section for...Ch. 9.4 - How would you approximate e0.6 using the Taylor...Ch. 9.4 - Prob. 4ECh. 9.4 - Prob. 5ECh. 9.4 - What condition must be met by a function f for it...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Limits Evaluate the following limits using Taylor...Ch. 9.4 - Power series for derivatives a. Differentiate the...Ch. 9.4 - Prob. 26ECh. 9.4 - Power series for derivatives a. Differentiate the...Ch. 9.4 - Power series for derivatives a. Differentiate the...Ch. 9.4 - Power series for derivatives a. Differentiate the...Ch. 9.4 - Power series for derivatives a. Differentiate the...Ch. 9.4 - Power series for derivatives a. Differentiate the...Ch. 9.4 - Power series for derivatives a. Differentiate the...Ch. 9.4 - Differential equations a. Find a power series for...Ch. 9.4 - Differential equations a. Find a power series for...Ch. 9.4 - Differential equations a. Find a power series for...Ch. 9.4 - Differential equations a. Find a power series for...Ch. 9.4 - Approximating definite integrals Use a Taylor...Ch. 9.4 - Approximating definite integrals Use a Taylor...Ch. 9.4 - Approximating definite integrals Use a Taylor...Ch. 9.4 - Approximating definite integrals Use a Taylor...Ch. 9.4 - Approximating definite integrals Use a Taylor...Ch. 9.4 - Approximating definite integrals Use a Taylor...Ch. 9.4 - Approximating definite integrals Use a Taylor...Ch. 9.4 - Approximating definite integrals Use a Taylor...Ch. 9.4 - Approximating real numbers Use an appropriate...Ch. 9.4 - Approximating real numbers Use an appropriate...Ch. 9.4 - Approximating real numbers Use an appropriate...Ch. 9.4 - Approximating real numbers Use an appropriate...Ch. 9.4 - Approximating real numbers Use an appropriate...Ch. 9.4 - Approximating real numbers Use an appropriate...Ch. 9.4 - Evaluating an infinite series Let f(x) = (ex ...Ch. 9.4 - Prob. 52ECh. 9.4 - Evaluating an infinite series Write the Taylor...Ch. 9.4 - Prob. 54ECh. 9.4 - Representing functions by power series Identify...Ch. 9.4 - Representing functions by power series Identify...Ch. 9.4 - Representing functions by power series Identify...Ch. 9.4 - Representing functions by power series Identify...Ch. 9.4 - Representing functions by power series Identify...Ch. 9.4 - Representing functions by power series Identify...Ch. 9.4 - Representing functions by power series Identify...Ch. 9.4 - Representing functions by power series Identify...Ch. 9.4 - Representing functions by power series Identify...Ch. 9.4 - Representing functions by power series Identify...Ch. 9.4 - Explain why or why not Determine whether the...Ch. 9.4 - Limits with a parameter Use Taylor series to...Ch. 9.4 - Limits with a parameter Use Taylor series to...Ch. 9.4 - Limits with a parameter Use Taylor series to...Ch. 9.4 - A limit by Taylor series Use Taylor series to...Ch. 9.4 - Prob. 70ECh. 9.4 - Prob. 71ECh. 9.4 - Prob. 72ECh. 9.4 - Prob. 73ECh. 9.4 - Prob. 74ECh. 9.4 - Prob. 75ECh. 9.4 - Prob. 76ECh. 9.4 - Elliptic integrals The period of a pendulum is...Ch. 9.4 - Prob. 78ECh. 9.4 - Fresnel integrals The theory of optics gives rise...Ch. 9.4 - Error function An essential function in statistics...Ch. 9.4 - Prob. 81ECh. 9.4 - Prob. 82ECh. 9.4 - Prob. 83ECh. 9.4 - Prob. 84ECh. 9.4 - Prob. 85ECh. 9 - Explain why or why not Determine whether the...Ch. 9 - Prob. 2RECh. 9 - Prob. 3RECh. 9 - Prob. 4RECh. 9 - Prob. 5RECh. 9 - Prob. 6RECh. 9 - Prob. 7RECh. 9 - Prob. 8RECh. 9 - Prob. 9RECh. 9 - Prob. 10RECh. 9 - Prob. 11RECh. 9 - Prob. 12RECh. 9 - Approximations a. Find the Taylor polynomials of...Ch. 9 - Estimating remainders Find the remainder term...Ch. 9 - Estimating remainders Find the remainder term...Ch. 9 - Estimating remainders Find the remainder term...Ch. 9 - Prob. 17RECh. 9 - Prob. 18RECh. 9 - Prob. 19RECh. 9 - Prob. 20RECh. 9 - Prob. 21RECh. 9 - Prob. 22RECh. 9 - Prob. 23RECh. 9 - Prob. 24RECh. 9 - Power series from the geometric series Use the...Ch. 9 - Power series from the geometric series Use the...Ch. 9 - Power series from the geometric series Use the...Ch. 9 - Prob. 28RECh. 9 - Prob. 29RECh. 9 - Power series from the geometric series Use the...Ch. 9 - Taylor series Write out the first three nonzero...Ch. 9 - Prob. 32RECh. 9 - Taylor series Write out the first three nonzero...Ch. 9 - Taylor series Write out the first three nonzero...Ch. 9 - Taylor series Write out the first three nonzero...Ch. 9 - Taylor series Write out the first three nonzero...Ch. 9 - Prob. 37RECh. 9 - Prob. 38RECh. 9 - Prob. 39RECh. 9 - Prob. 40RECh. 9 - Binomial series Write out the first three terms of...Ch. 9 - Prob. 42RECh. 9 - Prob. 43RECh. 9 - Prob. 44RECh. 9 - Convergence Write the remainder term Rn(x) for the...Ch. 9 - Prob. 46RECh. 9 - Limits by power series Use Taylor series to...Ch. 9 - Limits by power series Use Taylor series to...Ch. 9 - Limits by power series Use Taylor series to...Ch. 9 - Limits by power series Use Taylor series to...Ch. 9 - Limits by power series Use Taylor series to...Ch. 9 - Prob. 52RECh. 9 - Definite integrals by power series Use a Taylor...Ch. 9 - Prob. 54RECh. 9 - Definite integrals by power series Use a Taylor...Ch. 9 - Prob. 56RECh. 9 - Approximating real numbers Use an appropriate...Ch. 9 - Prob. 58RECh. 9 - Approximating real numbers Use an appropriate...Ch. 9 - Prob. 60RECh. 9 - Prob. 61RECh. 9 - Prob. 62RECh. 9 - Prob. 63RECh. 9 - Graphing Taylor polynomials Consider the function...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, calculus and related others by exploring similar questions and additional content below.Similar questions
- A polynomial of degree n I has exactly ____________________zero if a zero of multiplicity m is counted m times.arrow_forwardWhen we divide a polynomial P(x) by a divisor D(x), the Division Algorithm tells us that we can always obtain a quotient Q(x) and a remainder R(x). State two forms in which the result of this division can be written.arrow_forward
Recommended textbooks for you
- Algebra & Trigonometry with Analytic GeometryAlgebraISBN:9781133382119Author:SwokowskiPublisher:CengageAlgebra: Structure And Method, Book 1AlgebraISBN:9780395977224Author:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. ColePublisher:McDougal LittellCollege AlgebraAlgebraISBN:9781305115545Author:James Stewart, Lothar Redlin, Saleem WatsonPublisher:Cengage Learning
- Algebra and Trigonometry (MindTap Course List)AlgebraISBN:9781305071742Author:James Stewart, Lothar Redlin, Saleem WatsonPublisher:Cengage Learning
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:9781133382119
Author:Swokowski
Publisher:Cengage
Algebra: Structure And Method, Book 1
Algebra
ISBN:9780395977224
Author:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. Cole
Publisher:McDougal Littell
College Algebra
Algebra
ISBN:9781305115545
Author:James Stewart, Lothar Redlin, Saleem Watson
Publisher:Cengage Learning
Algebra and Trigonometry (MindTap Course List)
Algebra
ISBN:9781305071742
Author:James Stewart, Lothar Redlin, Saleem Watson
Publisher:Cengage Learning
Power Series; Author: Professor Dave Explains;https://www.youtube.com/watch?v=OxVBT83x8oc;License: Standard YouTube License, CC-BY
Power Series & Intervals of Convergence; Author: Dr. Trefor Bazett;https://www.youtube.com/watch?v=XHoRBh4hQNU;License: Standard YouTube License, CC-BY