# math

sin2x − cos2x − tan2x = 2sin2x − 2sin4x − 1/
1 − sin2x
for x = 45

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1. I can't quite make out your equation, but it is easy to plug in x=45

sin2x = sin90 = 1
sin4x = sin180 = 0

and so on.

If that still stumps you, show us how far you got, and try using some parentheses to make things clear, such as

1/(2-sin2x)

and say sin^2x or sin^2(x) if you mean sin squared of x instead of sin(2x)

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