Find the average value of the function f(x)=x−38 from x=5 to x=7. Write your answer as the logarithm of a single number in simplest form.Answer: ln(□)
Q. Find the average value of the function f(x)=x−38 from x=5 to x=7. Write your answer as the logarithm of a single number in simplest form.Answer: ln(□)
Set Up Integral: To find the average value of a continuous function f(x) on the interval [a,b], we use the formula:Average value = (1/(b−a))×∫abf(x)dxHere, a=5 and b=7, so we need to integrate f(x)=(8)/(x−3) from x=5 to x=7 and then multiply by 1/(7−5).
Solve Integral: First, let's set up the integral:Average value = (1/(7−5))×∫57x−38dxThis simplifies to:Average value = (1/2)×∫57x−38dx
Evaluate Integral: To integrate x−38, we recognize this as a simple logarithmic integration problem. The integral of u1du is ln∣u∣, so the integral of x−38dx is 8ln∣x−3∣. Now we need to evaluate this from x=5 to x=7.
Simplify Expression: Evaluating the integral, we get:(21)×[8ln∣7−3∣−8ln∣5−3∣]This simplifies to:(21)×[8ln(4)−8ln(2)]
Apply Logarithm Properties: We can simplify the expression using logarithm properties. The difference of logarithms is the logarithm of the quotient:(21)×8ln(24)Since 4/2 is 2, this further simplifies to:(21)×8ln(2)
Final Result: Multiplying through by (21)×8 gives us:4ln(2)This is the average value of the function f(x) from x=5 to x=7, expressed as the logarithm of a single number in simplest form.
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