Question

What two common identities are most useful for simplifying 2tanx/sin^2x + cos^2x - tan^2x?

Two identities are: sin^2x + cos^2x = 1 and tan2x=2tanx/1-tan^2x

Answer 1

2tanx/(sin^2x) + cos^2x - tan^2x?

or

2tanx/(sin^2x + cos^2x) - tan^2x?

or

2tanx/(sin^2x + cos^2x - tan^2x? )

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