Calculus/limits

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Question

Limits
Evaluate the given limit in the image

Answer
Evaluate the natural log of this limit , then raise e to your answer.

ln[(x^2+5x+6)/(x^2+2x+3)]^x  = xln[(x^2+5x+6)/(x^2+2x+3)]  =

ln[(x^2+5x+6)/(x^2+2x+3)]/ x^-1

use L'Hospital's Rule and simplify to find


lim ln[(x^2+5x+6)/(x^2+2x+3)]/ x^-1 = lim (3x^4+6x^3-3x^2)/(x^4+7x^3+19x^2+27x+18) = 3


The answer is therefore e^3  

Socrates

Expertise

I can answer questions from the standard four semester Calculus sequence. I am not prepared for questions on Tensor Calculus. Everything else is welcome. Derivatives, partial derivatives, ordinary differential equations, single and multiple integrals, change of variable, vector integration (Green`s Theorem, Stokes, and Gauss) and applications.

Experience

Ph.D. in Mathematics and many years teaching Calculus at state universities.

Education/Credentials
B.S. , M.S. , Ph.D.

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