Trig Identities Study Sheet

This study sheet has ten groups of trig identities for the basic trigonometry functions. These identities include the reciprocal and co-function relationships between trig functions. There are also half-angle and double angle identities, along with sum and product relationships. This table is an extremely useful thing to keep on hand when working with trig functions. Print a copy and keep it with your textbook today.

Trig Identities

Trig identities study sheet

This cheat sheet is optimized to fit on a single sheet of paper. Download the PDF version to print your own. Alternatively, get the trig identities study sheet as a slide in Google Apps for viewing anywhere or sharing with classmates or students.

Sine, Cosine, Tangent, Cotangent, Secant, Cosecant

The sine (sin), cosine (cos), tangent (tan), cotangent (cot), secant (sec), and cosecant (cos) of an angle θ are all ratios of the sides of a right triangle.

  • sin θ = opposite / hypotenuse
  • cos θ = adjacent / hypotenuse
  • tan θ = opposite / adjacent
  • cot θ = 1 / tan = adjacent / opposite
  • sec θ = 1 / cos = hypotenuse / adjacent
  • cos θ = 1 / sin = hypotenuse / opposite