Knowledge of Functions
Khan academy
https://www.khanacademy.org/math/trigonometry/functions_and_graphs/function_introduction/v/domain-of-a-function
https://www.khanacademy.org/math/trigonometry/functions_and_graphs/function_introduction/e/domain_of_a_function
Mathplanet
http://www.mathplanet.com/education/algebra-2/polynomial-functions/basic-knowledge-of-polynomial-functions
Finite Mathematics
https://finitemathematics.wikispaces.hcpss.org/Unit+4+Polynomial+Functions
University of Arizona
http://www.biology.arizona.edu/biomath/tutorials/polynomial/graphingpolynomials.html
Khan academy
https://www.khanacademy.org/math/trigonometry/functions_and_graphs/function_introduction/v/domain-of-a-function
https://www.khanacademy.org/math/trigonometry/functions_and_graphs/function_introduction/e/domain_of_a_function
Mathplanet
http://www.mathplanet.com/education/algebra-2/polynomial-functions/basic-knowledge-of-polynomial-functions
Finite Mathematics
https://finitemathematics.wikispaces.hcpss.org/Unit+4+Polynomial+Functions
University of Arizona
http://www.biology.arizona.edu/biomath/tutorials/polynomial/graphingpolynomials.html