Help Basic logarithmic differentiation question.

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SUMMARY

The discussion focuses on finding the equation of the tangent line to the curve defined by y=8^x at the point where x=1/2. The derivative is calculated as dy/dx=8^x(ln8), which evaluates to approximately 5.9 at x=1/2. The user initially arrives at the equation 5.9x - y - 0.15 = 0, but the correct tangent line equation is y=(6√2(ln2))x + √2(2-3ln2). Key insights include the importance of not rounding answers and simplifying expressions involving roots.

PREREQUISITES
  • Understanding of basic differentiation rules
  • Familiarity with exponential functions
  • Knowledge of logarithmic properties, specifically natural logarithms
  • Ability to manipulate algebraic expressions involving roots
NEXT STEPS
  • Study the application of the product rule in differentiation
  • Learn about the properties of logarithms, particularly ln(a^b)
  • Explore techniques for simplifying expressions with roots
  • Practice finding tangent lines for various exponential functions
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Students studying calculus, particularly those focusing on differentiation and tangent line problems, as well as educators looking for examples of exponential function analysis.

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Homework Statement


Determine the equation of the line that is tangent to y=8^x at the point on the curve x=1/2.

Homework Equations


Differentiation Rules
m=y2-y1/x2-x1

The Attempt at a Solution


y=8^x
dy/dx=8^x(ln8)
=8^0.5(ln8)
=5.9

y=8^x
=8^0.5
=2.8

5.9=y-2.8/x-0.5
5.9x-y-0.15=0 (My answer)

y=(6root2(ln2))x + root2(2-3ln2) (Real Answer)

How does this answer even make sense, I don't know where to go from here.
 
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Hints:
Don't round your answers; leave them the way they are.
ln8 = ln(2^3)=3ln2
root8 = 2root2
You're doing the problem correctly, but you may want to avoid rounding and reduce your expressions (for example, turn all the root8's into 2root2's).
 

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