Question

the value of sin(A+B)×sin(A-B)=?​

Answer 1

Answer:

Sin (a + b) . Sin (a - b) = sin²a - sin²b

Step-by-step explanation:

(Sin a . Cos b + Cos a .sin b)(sin a . Cos b - cos a sin b)

= Sin²a cos²a - cos²a sin²b

= Sin²a (1 - sin²a) - (1 - sin²a)

= sin²a - sin²b