Maths

Interactive lessons for trigonometry, linear algebra, and calculus. Drag angles on the unit circle, multiply 2×2 matrices, watch a tangent line chase a curve, and slide Riemann sums toward an integral. Built to study from — not a textbook reprint.

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Start with trig if you want angle, sin/cos, and SOHCAHTOA in your fingers, then the unit circle trainer for the sixteen exact values. Linear algebra if you want matrices and vectors on a plane. Calculus when you are ready for rates of change, areas under curves, and limit intuition.

Trigonometry

Unit circle · SOHCAHTOA

Click or drag the angle. Live sin, cos, tan. Degree/radian toggle, common-angle presets, and a short identity / SOHCAHTOA check.

Unit circle trainer

Memory · exact values

Drill 0°, 30°, 45° through 330°. Angle to point, point to angle, degrees and radians, sin/cos/tan, and tap the circle.

Linear algebra

Matrices · vectors · eigenvalues

2×2 multiply with a visual, determinant and inverse when it exists, 2D vector add/scale on a canvas, and an optional eigenvalue stretch.

Calculus

Derivative · integral · limit

Tangent line on a selectable f(x), Riemann-sum slider for a definite integral, and a limit-intuition demo as x approaches a point.

How to use

Touch and mouse. Canvases accept drag and tap; controls are large enough for phones.
Read the readout. Numbers update live — treat them as the worked example next to the picture.
Change the inputs. Presets and sliders are there so you can ask “what if” without rewriting the page.
Nearby desks. Pair with Science, the Standard Model particle grid, the Gravity desk (inverse-square and spacetime literacy), Electronics, and the All pages when you want applications.

Nearby

Trigonometry — unit circle Unit circle trainer Linear algebra — matrices & vectors Calculus — derivative, integral, limit Science — where we stand Standard Model — quarks, leptons, bosons Gravity — weight, Newton, Einstein Electronics — converters & circuits All pages

Educational interactive maths for self-study. Definitions and identities are standard school/early-college material written in original wording. Not a substitute for coursework, exams, or textbooks. Verify against your syllabus.