(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A scientist predicted that the population of fish in a lake could be modeled by the function f(t)= 40t/(t^2+1), where t is given in days. The function that actually models the fish population is g(t)=45t/(t^2+8t+7). Determine where g(t)>f(t).

2. Relevant equations

f(t)= 40t/(t^2+1)

g(t)=45t/(t^2+8t+7)

g(t)>f(t)

3. The attempt at a solution

g(t)>f(t)

45t/(t^2+8t+7)>40t/(t^2+1)

45t/(t+1)(t+7)-40t/(t^2+1)>0

Find LCD by multiplying 1

45t/(t+1)(t+7) x (t^2+1)/(t^2+1)-40t/(t^2+1) x (t+7)(t+1)/(t+7)(t+1) > 0

Simplifies to

(5t^3-320t^2-235t)/(t+1)(t+7)(t^2+1)

5t(t^2-64t-47)/(t+1)(t+7)(t^2+1) >0

Am i doing this correct? I don't know what to do next.

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# Homework Help: Help in need! : Rational functions problem

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