Prove the trigonometric identity Use sumdifference identitie

Prove the trigonometric identity. (Use sum/difference identities at some point.)

3) sin(9-u)sin(8 + )s sin\"(8)-sin\"(a)

sin (+w)sin(-w)

= 1/2 [ cos(+w-+w) - cos(-w++w) ]

= 1/2 [ cos 2w - cos 2]

= 1/2 [ 1 - 2sin²w - 1 + 2sin² ]

= 1/2 *2[sin² - sin²w]

= sin² - sin²w

Hence proved.

$Prove the trigonometric identity. (Use sum/difference identities at some point.) 3) sin(9-u)sin(8 + )s sin\$