Precalculus Midterm #2 Review
Precalculus Midterm #2 Review
Background Information
- §A.4: Synthetic Division (dividing by x-c)
- §A.5: Rational Expressions (simplifying and arithmetic)
- §A.7: Complex Numbers (meaning and arithmetic)
Polynomials and Rational Functions
- §4.1: Polynomial Basics
- degree, power functions, zeroes/roots, multiplicity, end behavior, turning points
- effect of degree, roots, and multiplicity on graph of function
- §4.5: Real Roots of a Polynomial
- use the Rational Roots Theorem to find possible roots; calculate to see what works
- divide out a factor to determine what's left
- fully factor to find all roots, then graph
- §4.6: Complex Roots of a Polynomial
- factor out any real roots as usual
- if what's left is a quadratic, use the quadratic formula
- complex roots should come in conjugate pairs
- §4.2: Rational Function Basics
- general appearance, asymptotes, gaps, end behavior
- §4.3: Graphing Rational Functions
- factor everything, identify gaps, cancel out factors as needed
- find vertical asymptotes (denominator) and x-intercepts (numerator)
- find horizontal or oblique asymptote and determine if it is ever crossed
- investigate end behavior and behavior near vertical asymptotes
- §4.4: Polynomial and Rational Inequalities
- manipulate inequality to put everything on one side and 0 on the other
- find all roots and vertical asymptotes: these are potential boundary points
- test sample points between them to determine where function is positive or negative
Composition, Inverse Functions, Exponents, Logarithms
- §5.1: Function Composition
- composition as a binary operation on functions
- notation; finding fog(x) and gof(x) given f(x) and g(x)
- §5.2: Inverse Functions
- definition of inverse function; checking if functions are inverses of each other
- one-to-one functions; horizontal line test; some inverses aren't functions
- finding inverse of a function by interchanging input and output
- graphing a function and its inverse
- §5.3: Exponential Functions
- meaning and properties of exponents (including negatives, fractions, irrationals)
- graphing exponential functions: domain, range, asymptote, standard transformations
- solving simple exponential equations (rewrite with a common base)
- the number e and its use as a universal base
- §5.4: Logarithmic Functions
- definition of a logarithm as the inverse function of exponentiation
- converting between exponential form and logarithmic form
- common logarithms (base 10) and natural logarithms (base e)
- graphing logarithmic functions: domain, range, asymptote, standard transformations
- solving simple logarithmic equations (rewrite in exponential form)
- §5.5: Properties of Logarithms
- product rule, quotient rule, power rule, change-of-base formula
- condensing or expanding logarithmic expressions
- §5.6: Solving Exponential and Logarithmic Equations
- if variable is in exponent, taking the logarithm of both sides is often useful
- if variable is in logarithm, try rewriting in exponential form
- §5.8: Applications in Physics and Biology
- exponential growth (decay): P(t) = P0·ert, where r is a positive (negative) constant
- population growth: predict when a population will reach a certain size
- radioactive decay: understand meaning of "half-life" and how to calculate it
- heating and cooling: T(t) = Troom + (T0 - Troom)·ekt, where k is a negative constant
- in general: plug in known data and solve for unknown constants
- pay close attention to asymptotes!
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