A 4-page visual revision sheet for Trigonometry - 1, written for Class 11 Maharashtra HSC Mathematics. Formulas, diagrams and the traps that cost marks, laid out to be read the night before rather than the term before. Free, and it opens inside CapCompass.
Page 1 as PDFA preview of page 1 — all 4 pages open full size in the app.
Trigonometry - 1 in one look
the unit circle's ratios, extended to any angle at all
Trigonometric Functions and the Unit Circle
circle radius r, centre at the origin: P(x,y) lies on the terminal ray of angle θ
cosθ=x/r, sinθ=y/r
on the unit circle (r=1), P(x,y) is just P(cosθ,sinθ) directly
ratios are the SAME on the whole terminal ray: independent of r, identical for coterminal angles
Six ratios from x, y, r
cosinecosθ=x/r
sinesinθ=y/r
tangenttanθ=y/x
cosecantoperatornamecosecθ=r/y
secantsecθ=r/x
cotangentcotθ=x/y
Where a ratio breaks down
cosθ=0, i.e. θ=(2n+1)π/2 — tanθ and secθ are undefined there
sinθ=0, i.e. θ=nπ — cotθ and cosecθ are undefined there
θ=0 — sinθ=0, cosθ=1, tanθ=0: the base case every identity builds from
θ=90° — cosθ=0, sinθ=1: tanθ and secθ blow up right here
Page 1 of 4. The full sheet, all 4 pages, opens free in the app.
These notes are not a standalone PDF. CapCompass plans Mathematics chapter by chapter against your real exam dates and free hours, and when the plan reaches Trigonometry - 1 the sheet opens inside the study block itself — at the page covering the sub-topic that block is on, with the timer still running. Revision arrives at the moment the plan says revise, instead of having to be gone looking for.