Answer:
[tex]\left(sin\theta -cos\:a\right)\left(cos\:a+sin\theta \right)[/tex]
(sin(θ)-cos(a))(cos(a)+sin(0))
[tex]\mathrm{Apply\:Difference\:of\:Two\:Squares\:Formula:\:}\left(a-b\right)\left(a+b\right)=a^2-b^2[/tex]
a=sin(θ),b=cos(a)
= sin²(θ)-cos²(a)
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hope it helps...
have a great day!!
