Math, asked by Anvijaws, 4 months ago

(sina+cosa-1)(sina+cosa+1)
Please simplify it.

Answers

Answered by BrainlyKingdom
2

\sf{\left(\sin \left(a\right)+\cos \left(a\right)-1\right)\left(\sin \left(a\right)+\cos \left(a\right)+1\right)}

=\sin \left(a\right)\sin \left(a\right)+\sin \left(a\right)\cos \left(a\right)+\sin \left(a\right)\cdot \:1+\cos \left(a\right)\sin \left(a\right)+\cos \left(a\right)\cos \left(a\right)+\cos \left(a\right)\cdot \:1=\sin \left(a\right)\sin \left(a\right)+\sin \left(a\right)\cos \left(a\right)+\sin \left(a\right)\cdot \:1+\cos \left(a\right)\sin \left(a\right)+\cos \left(a\right)\cos \left(a\right)+\cos \left(a\right)\cdot \:1

=\sin \left(a\right)\sin \left(a\right)+\sin \left(a\right)\cos \left(a\right)+1\cdot \sin \left(a\right)+\cos \left(a\right)\sin \left(a\right)+\cos \left(a\right)\cos \left(a\right)+1\cos \left(a\right)-1\cdot \sin \left(a\right)-1\cdot \cos \left(a\right)-1\cdot \:1

=\sin \left(a\right)\cos \left(a\right)+\cos \left(a\right)\sin \left(a\right)+\cos \left(a\right)\cos \left(a\right)+1\cdot \cos \left(a\right)-1\cdot \cos \left(a\right)+\sin \left(a\right)\sin \left(a\right)+1\cdot \sin \left(a\right)-1\cdot \sin \left(a\right)-1\cdot \:1

=2\cos \left(a\right)\sin \left(a\right)+\cos \left(a\right)\cos \left(a\right)+1\cdot \cos \left(a\right)-1\cdot \cos \left(a\right)+\sin \left(a\right)\sin \left(a\right)+1\cdot \sin \left(a\right)-1\cdot \sin \left(a\right)-1\cdot \:1

\sf{=2\cos \left(a\right)\sin \left(a\right)+\cos \left(a\right)\cos \left(a\right)+\sin \left(a\right)\sin \left(a\right)+1\cdot \sin \left(a\right)-1\cdot \sin \left(a\right)-1\cdot \:1}

\sf{=2\cos \left(a\right)\sin \left(a\right)+\cos \left(a\right)\cos \left(a\right)+\sin \left(a\right)\sin \left(a\right)-1\cdot \:1}

\sf{=2\cos \left(a\right)\sin \left(a\right)+\cos ^2\left(a\right)+\sin ^2\left(a\right)-1}

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