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Calculus/Verify the Identity

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Expert: - 3/5/2009


Question
cosx +sinx*tanx = secx


Answer
Put in tanx = sinx / cosx.

Multiply the cosx by cosx/cosx so you have cos²x/cos.

Combine the fractions since they have a common denominator of cosx.

Know that the new top, sin²x+cos²x, is really 1.

Know that 1/cosx = secx.

You've got it.

Calculus

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Any kind of calculus question you want. I also have answered some questions in Physics (mass, momentum, falling bodies), Chemistry (charge, reactions, symbols, molecules), and Biology.

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