# Can you find the mistake?

Level pending

Which step of the given fallacy contains the mistake?

sin90°=1

sin^2(90°) =1

3sin^2(90°)=3

2sin^2(90°) + sin^2(90°) = 2+1

2sin^2(90°) - 2 = - sin^2(90°) + 1

2{sin^2(90°) - 1 } = - 1{ sin^2(90°) - 1 }

  2  =  - 1

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