Class 10 Trignometry

• ​Basic trignometry

• ​Trignometry ratios of common angles

• ​Trignometry ratios of complement angle

• ​Trignometry identities

• ​Question

​Trignometry can only apply to right angle triangle.

1. ​Height is side taken opposite to angle taken.

2. ​Base is side on which angle taken lie,

3. ​Hypotenuse is the longest side of a right-angled triangle.

4. ​Sin,cos ratios can never be an improper fraction i.e. denominator is always larger than numerator.

5. ​Sec,cosec can never be a proper fraction.

6. ​Learn the ratios in order Sin,Cos,Tan.

​1st ratio is of sin that is L/K or P/H remember the order of ratios and trick

​Hence proved.

​​Prove that cot x = cos x/sin x

​Ex 8.1 NCERT.

1. ​Learn the angles in order 0,30,45,60,90.

2. ​Now as per order take the first line as sin.

3. Now write 0,1,2,3,4 in order beneath angles.​

4. ​Now divide the raw in 4 i.e. 0, 1/4 , 2/4 , 3/4 , 4/4

5. ​Than take square root of whole raw i.e. 0 , 1/2 , ​​​

​6. This is the first raw that is sin function at diffrent angles.

7. ​Now write inverse of first raw to find cos.

​8. Now divide first and second raw for tan.

​9. And the other threes are reciprocal of first three so basically reciprocal

​Q.1 Find sin 45 + cos 45.

​Q2.Find tan 60-cot 30.

​Do NCERT ex 8.2

​Similiarly find all other

ratios

​Do ex. 8.3 NCERT

​Prove

​Similiarly divide eq. with

​ for II eq. and for III

​eq. to prove it.