Common Core Math - HS Functions
Lesson Plan
Prove growth properties of functions
Goals / Objectives
Prove algebraically that for f(x) = mx + b, the difference f(x + d) - f(x) = md for any equal spacing d, showing the result is independent of x
Prove algebraically that for g(x) = a * b^x, the ratio g(x + d) / g(x) = b^d for any equal spacing d, showing the result is independent of x
Explain why the constant difference property is equivalent to a constant rate of change (slope)
Explain why the constant ratio property is equivalent to a constant growth/decay factor (base)
Use the proofs to determine whether a given function is linear or exponential without relying solely on tables of values
Connect the algebraic proofs to numerical examples by verifying the formulas with specific values of x and d
Standards
HSF.LE.A.1.a
HSF.LE.A.1.a: Prove that linear functions grow by equal differences over equal intervals, and that exponential functions grow by equal factors over equal intervals.
Academic Vocabulary
Not in our source material
Materials
Remediation
Enrichment
Accommodations
Not in our source material