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Revise: Logarithmic and Exponential Functions

Graphs of logarithmic and exponential functions, their transformations, and their derivatives.

The Graph of an Exponential Function

y=bˣ: range (0,∞), passes through (0,1), asymptote y=0.

2⁻²=0.25.

The Graph of a Logarithmic Function

y=log_b(x): inverse of bˣ, domain (0,∞).

log₂(8)=3.

Transformations of Exponential and Logarithmic Graphs

Vertical shift D also moves the asymptote.

3ˣ+6 → asymptote y=6.

The Derivative of eˣ

d/dx[eˣ] = eˣ — its own derivative.

3eˣ → f'(0)=3.

The Derivative of General Exponential Functions

d/dx[bˣ] = bˣ·ln(b).

2ˣ → f'(0)≈0.693.

The Derivative of the Natural Logarithm

d/dx[lnx] = 1/x.

5lnx → f'(2)=2.5.

The Derivative of General Logarithmic Functions

d/dx[log_b x] = 1/(x ln b).

log₂(x) → f'(1)≈1.443.