Algebra 2 to Reiny

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in the one you helped me with, where did this come from: Where did this part come from?
- (sin^2Ø + cos^2Ø)

  • Algebra 2 to Reiny -

    you should have come across the identity
    sin^2Ø + cos^2Ø = 1 , called the Pythagorean

    so I replaced 1 with that expression

  • Algebra 2 to Reiny -

    oh. I didn't think to connect it with that. Thank you for pointing it out to me.

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