Some formulas of trigonometry you can see in below.

There are many formulas in trigonometry. You can see below some formulas of trigonometry.

- sin (A+B) = sinA cosB + cosA sinB
- sin (A-B)= sinA cosB – cosA sinB
- cos (A+B)= cosA cosB + sinA sinB
- cos (A-B)= cosA cosB + sinA sinB
- sin C + sin D= 2sin (C+D)/2 * cos (C-D)/2

- sin C – sin D= 2cos(C+D)/2 * sin(C-D)/2

- cos C + cos D= 2cos(C+D)/2 * cos(C-D)/2

- cos C – cos D= 2sin(C+D)/2 * sin(C-D)/2

- sin 2Ɵ= 2sinƟ cosƟ
- cos
2Ɵ= cos
^{2}Ɵ-sin^{2}Ɵ - cos 3Ɵ= 4cos
^{3}Ɵ-3cosƟ - sin
3Ɵ= 3sinƟ-4sin
^{3}Ɵ - Sin
^{2}Ɵ+cos^{2}Ɵ= 1 - Sec
^{2}Ɵ= 1+tan^{2}Ɵ - Cosec
^{2}Ɵ= 1+cot^{2}Ɵ

This was the formulas of trigonometry.I hope you learned.