SOLUTION: Prove the trigonometric identity 2sinē(θ)-1 = sin⁴(θ)-cos⁴(θ)

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Question 945607: Prove the trigonometric identity
2sinē(θ)-1 = sin⁴(θ)-cos⁴(θ)
Answer by Edwin McCravy(20059) About Me  (Show Source):
You can put this solution on YOUR website!
2sinē(θ)-1 = sin⁴(θ)-cos⁴(θ)
           = [sinē(θ)-cosē(θ)][sinē(θ)+cosē(θ)]
           = [sinē(θ)-cosē(θ)][1]
           = sinē(θ)-cosē(θ)
           = sinē(θ)-[1-sinē(θ)]
           = sinē(θ)-1+sinē(θ)
           = 2sinē(θ)-1 

Edwin