Relationships-Trigonometric Ratios

Basic Relationships

(tan theta ) = (sin theta over {cos theta })

(cot theta ) = (cos theta over {sin theta })

(cosec theta ) = (1 over {sin theta })

(sec theta ) = (1 over {cos theta })

(sin^2 theta ) + (cos^2 theta ) = 1

1 + (cot^2 theta ) = (cosec^2 theta )

1 + (tan^2 theta ) = (sec^2 theta )

(sin (90^ {circ} – theta)) = (cos theta)

(cos (90^ {circ} – theta)) = (sin theta)

(cot (90^ {circ} – theta)) = (tan theta)

(tan (90^ {circ} – theta)) = (cot theta)

(cosec (90^ {circ} – theta)) = (sec theta)

(sec (90^ {circ} – theta)) = (cosec theta)