## 1. Trigonometric Ratios

### 1.1. [email protected]=P/H,[email protected]=H/P [email protected]=B/H,[email protected]=H/B [email protected]=P/B,[email protected]=B/P

1.1.1. Trick to remember is : Pandit Badari Prasad Har Har Bole Sona Chadi Tole

## 2. Trigonometric Ratios with Special Angles

### 2.1. 0 1/2 1/√2 √3/2 1 1 √3/2 1/√2 1/2 0 0 1/√3 1 √3 N N 2 √2 2/√3 1 1 2/√3 √2 2 N N √3 1 1/√3 0

2.1.1. Tricks to remember : For first count 0 to 4 write 4 in denominator and put √on both. For second write the first in backward direction. For third divide first and second. For fourth write inverse of first. For fifth write inverse of second. For sixth write inverse of third.

## 3. Trigonometric Identities

### 3.1. 1) Cos^2 A+Sin^2 A = 1 2) 1+Tan^2 A = Sec^2 A 3) Cot^2A+1=Cosec^2A

3.1.1. Trick is Hexagonal Shape

## 4. Trigonometric Ratios of Complementary Angles

### 4.1. Sin (90 - A) = Cos A Tan (90 - A) = Cot A Sec (90 - A) = Cosec A Cos (90 - A) = Sin A Cot (90 - A) = Tan A Cosec (90 - A) = Sec A

4.1.1. Trick is: Remember 'Co' and first three part before = . Add Co to first three part and we have the after part of them. Write the after part term on first now . Then remove Co from it to get the last three part.