Advanced Math/Math

Advertisement


Question
I was working on this practice problem and can't get the right answer. It is:

If f(x)=(x^(2)+4)(x^(3)-2), write an equation for the tangent line to f(x) at x=1

Thank you for your assistance!

Answer
y = (x+4)(x-2) = x⁵+4x-2x-8
dy/dx = 5x⁴+12x-4x
slope at (1, -5) = 51⁴+121-41 = 13

point-slope equation for line of slope = 13 that passes through (1, -5):
y+5 = 13(x-1)

in slope-intercept form:
y = 13x-18

https://www.flickr.com/photos/dwread/15582170640/

Advanced Math

All Answers


Answers by Expert:


Ask Experts

Volunteer


Janet Yang

Expertise

I can answer questions in Algebra, Basic Math, Calculus, Differential Equations, Geometry, Number Theory, and Word Problems. I would not feel comfortable answering questions in Probability and Statistics or Topology because I have not studied these in depth.

Experience

I tutor students (fifth through twelfth grades) and am a Top Contributor on Yahoo!Answers with over 24,000 math solutions.

Publications
Co-author of An Outline of Scientific Writing: For Researchers With English as a Foreign Language

Education/Credentials
I have a Bachelor's degree in Applied Mathematics from the University of California at Berkeley.

Past/Present Clients
George White Elementary School. Homework Help program at the Ridgewood Public Library, Ridgewood, NJ. Individual students.

©2016 About.com. All rights reserved.