wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

all formulae of chapter into to trignmetry

Open in App
Solution

Trigonometry is used to analyze the relationship between angles heights and lengths of triangles. The fundamentals of trigonometry are introduced in class 10 and have been summarized below.
In a right-angled triangle, the Pythagoras theorem states

(perpendicular )2 + ( base )2 = ( hypotenuse )2

There are some properties pertaining to the right-angled triangle. It is to be noted that in the following formulas, P stands for perpendicular, B stands for base and H stands for the hypotenuse.

  1. SinA = P / H
  2. CosA = B / H
  3. TanA = P / B
  4. CotA = B / P
  5. CosecA = H / P
  6. SecA = H/B
  7. Sin2A + Cos2A = 1
  8. Tan2A + 1 = Sec2A

Cot2A + 1 = Cosec2A

In order to find a relationship between various trigonometric identities, there are some important formulas:
1. TanA = SinA / CosA
2. CotA = CosA / SinA
3. CosecA = 1 / SinA
4. SecA = 1 / CosA

There are some formulas that are very crucial to solving higher level sums.

  1. Sin (A +B) =SinA . CosB + CosA . SinB
  2. Sin (A – B) = SinA . CosB – CosA . SinB
  3. Cos (A + B) = CosA . CosB – SinA . SinB
  4. Cos (A – B) = CosA. CosB + SinA . SinB
  5. Tan (A + B) = TanA + TanB / 1 – TanA . TanB
  6. Tan (A – B) = TanA –TanB / 1 + TanA . TanB
  7. Sin ( A + B) . Sin (A – B) = Sin2A – Sin2B = Cos2B – Cos2A
  8. Cos (A + B) . Cos (A – B) = Cos2A – Sin2B = Cos2B – Sin2A
  9. Sin2A = 2 . SinA . CosA = 2 . TanA / (1 + Tan2A)
  10. Cos2A = Cos2A – Sin2A = 1 – 2Sin2A = 2Cos2A – 1 = (1 – Tan2A) / (1 + Tan2A)
  11. Tan2A = 2TanA / (1 – Tan2A)
  12. Sin3A = 3 . SinA – 4 . Sin3A
  13. Cos3A = 4 . Cos3A – 3 . CosA
  14. Tan3A = (3TanA – Tan3A) / (1 – 3Tan2A)
  15. SinA + SinB = 2 Sin (A + B)/2 Cos (A – B)/2
  16. SinA – SinB = 2 Sin (A – B)/2 Cos (A + B)/2
  17. CosA + CosB = 2 Cos(A – B)/2 Cos (A + B)/2
  18. CosA – CosB = 2 Sin(B – A)/2 Sin (A + B)/2
  19. TanA + TanB = Sin (A + B) / CosA . CosB
  20. SinA CosB = Sin (A + B) + Sin (A – B)
  21. CosA SinB = Sin (A + B) – Sin (A – B)
  22. CosA CosB = Cos (A + B) + Cos (A – B)
  23. SinA SinB = Cos (A – B) – Cos (A + B)

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Range of Trigonometric Ratios from 0 to 90
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon