**Trigonometric Ratios CBSE NCERT Solutions Chapter 8 Exercise 8.1 Question 9**

**9.** In , right angled at B, if tan A = , find the value of

**(i) sin A cos C + cos A sin C**

**(ii) cos A cos C - sin A sin C**

**Solution:**

tan A =

tan A = **(Side Opposite to Angle A) / (Side Adjacent to Angle A)** =

Let BC = 1.k and AB = as we are given that

**Using Pythagoras Theorem on , we get**

sin A = (Side Opposite to Angle A) / (Hypotenuse) =

cos C = (Side Adjacent to Angle C) / (Hypotenuse) =

cos A = (Side Adjancet to Angle A) / (Hypotenuse) =

sin C = (Side Opposite to Angle C) / (Hypotenuse) =

**(i) **

**sin A cos C + cos A sin C = **

=

**(ii)**

** cos A cos C - sin A sin C = **