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Question
how would you solve cosx+sinxtanx=2?
As a 1st step, note that tanx = sinx / cosx.
This makes the equation into cosx + sin²x/cosx = 2.
For the 2nd step, multiply the entire equation by cosx.
This gives cos²x + sin²x = 2cosx.
For the 3rd step, remember sin²x + cos²x = 1?
Well, the left side is the reverse, and is still 1.
So we have 1 = 2cosx.
For the 4th step, divide both sides by 2.
This gives 1/2 = cosx.
Finally, this puts x = ±60° or x = 60° and x = 300°.
In radians, that is x = π/3 and x = 5π/3.
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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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