Trigonometry revisions - boards

Formulas

Rad to D

squred

Cos (x+y)

cosx cosy - sinx siny

cos (x-y)

cosx cosy - sinx siny

sin(x+y)

sinx cosy + cosx siny

sin (x-y)

sinx cosy - cosx siny

tan (x + y)

tanx +tan y

---

1- tanx tany

tan (x-y)

tanx-tany

---

1+tanx tany

cot(x+y)

cotx coty-1

---

coty +cotx

cot (x-y)

cotx coty +1

---

coty - cotx

cos2x

cos²x-sin²x 2cos² x -1 1- 2sin² x 1- tan² x

---

1+ tan²x

sin2x

2sin x cos x. 2tanx

---

1+ tan² x

tan 2x

2 tanx

---

1+ tan² x

sin 3x

3sinx - 4 sin³ x

cos 3 x

4 cos³ x - 3 cos x

tan 3x

3tanx - tan³ x

---

1-3 tan² x

cosx + cos y

cosx- cosy

Sinx + siny

sinx - siny

1. cos(x+y) +cos(x-y)

cos(x+y) -cos(x-y)

sin(x+y) + cos(x-y)

sin(x+y) - cos(x-y)

General

Sin ratios

Derivation

Imp

B