Mathlean · Online math workspace
Trigonometric expansion calculator
Expand supported trigonometric multiple-angle expressions.
How to use this calculator
Edit TrigExpand(sin(2x)); the double-angle identity gives 2 sin(x) cos(x).
Tap the math below to edit it and see the result. Once a result is ready, press Tab on a hardware keyboard to accept it. Outside a matrix, Return completes the line; the phone math keyboard has the same Return action.
Try it here
Interactive tools require JavaScript. You can read the guide and example without it.
What to know
Identities assume compatible angle conventions; symbolic expansion is not numerical angle conversion.
Mathlean combines visual mathematical input with computation and canvas tools. Results depend on the expression and available engine support; check important answers independently.