Learning preferences

Make learning more comfortable. Changes apply immediately.

Enlarges page content, including diagrams and their labels. You can also use your browser’s zoom.

Choose the colours that are easiest for you to distinguish. Applies to lesson diagrams and lab plots. Labels, shapes, hatching and line patterns also distinguish meanings. Source photographs and raw image brightness stay unchanged; mask-only views are available for image overlays.

ExampleComparisonSample link

Saved in this browser on this device. Preferences are separate from progress backups.

Mathematics · unit version 1

Precalculus: periodic and reciprocal graph evidence

Construct complete periodic graphs, compare finite rates and fit competing sinusoidal periods using new evidence. School algebra, unit-circle coordinates and graph reading suffice; calculus is not required.

Open any lesson. Completion records participation; automatic practice checks and human judgment of written arguments are separate. This unit retains its own versioned requirements.

Readiness and preparation

Check your starting point

Try these short questions on paper, then compare your reasoning. They are optional self-checks, not a placement score or a navigation requirement. Use a targeted review when useful and return with your browser’s Back control.

How do a sinusoid’s period and amplitude differ?

Horizontal repetition and vertical variation describe different features.

Compare reasoning and find a refresher

The period is the smallest positive input shift that repeats a nonconstant sinusoid. Its amplitude is half the difference between its maximum and minimum outputs. Their units follow the input and output respectively.

Review sinusoidal landmarks and transformations

Where is a trigonometric quotient undefined?

A graph must retain exclusions and separate branches.

Compare reasoning and find a refresher

Check its original denominator: tangent and secant require nonzero cosine; cotangent and cosecant require nonzero sine. A plotting line must never join branches across an excluded input.

Review tangent and reciprocal domains

Loading saved mathematics work…

Periodic graph evidence: mixed practice

The mixed assessment has separate response history and review criteria; it does not change lesson participation records.

Lesson sequence

Each linked lesson opens on its own page. Expand its details here when you want to check the objectives before choosing.

  1. Recover sinusoidal shape and changing rates

    Lesson details and objectives

    Construct a complete sinusoid and separate output level, motion direction and concavity.

    • Recover amplitude, midline, period and phase from a stipulated full sinusoidal graph.
    • Compare finite secant rates and describe increasing/decreasing behavior separately from changing rate.
    • Justify sinusoidal concavity without derivatives and distinguish assumed shape from sparse observations.

    6 practice tasks.

  2. Fit competing periods and test new predictions

    Lesson details and objectives

    Execute conditional periodic regression and expose ambiguity with unused inputs.

    • Fit noisy observations for two supplied candidate periods, retaining coefficients, phase conventions and original-scale errors.
    • Use fresh predictions and uncertainty to compare candidates without claiming a global period search.
    • Diagnose aliasing, flat phase and unresolved sampling designs.

    6 practice tasks.

  3. Construct tangent and cotangent branches

    Lesson details and objectives

    Track transformed asymptotes and solve inequalities across all admissible intervals.

    • Construct complete transformed tangent and cotangent branches from exact landmarks and all-domain exclusions.
    • Account for negative input/output scales in periods, direction and infinite limits.
    • Solve quotient inequalities using branch signs and explicit excluded points.

    6 practice tasks.

  4. Construct secant and cosecant graphs

    Lesson details and objectives

    Use reciprocal geometry to recover disconnected ranges, branch vertices and direction.

    • Construct transformed secant and cosecant graphs with complete asymptote and extremum information.
    • Explain branch monotonicity and range changes under shifts and negative scales without derivatives.
    • Recover graph parameters and solve reciprocal inequalities with sign-aware domain checks.

    6 practice tasks.