#proving trig identities

36 messages · Page 1 of 1 (latest)

lethal current
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use (a + b)^2 = a^2 + 2ab + b^2

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(cot(x)+1)^2

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expand this

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same with the other one

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technically you could argue for taking square root of both sides

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that would be simpler actually

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sometimes first thing you think of is slower

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(the new idea is changing a^2*b^2 to (ab)^2)

lethal current
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you have something squared times something squared

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move both into one parentheses

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when you bring it inside the squared

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you unsquare it

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otherwise when you multiply it out it will become to the 4th power

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yep

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then it wouldn't simplify

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you can leave it as tanx sinx

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remove the ^2 first then bring it in

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also works

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x^2 times (x+1)^2 is (xx + x)^2

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so you can

lethal current
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yeah if you divide both top and bottom by cos(y)cos(x) that is what you will get

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you can multiply things

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the other way to do this would be changing the top to sin(x + y) and the bottom to sin(x - y)

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i think

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but that wouldnt get you to the answer it seems

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ah

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where you get it from is you see that multiplying it would get you to the answer

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you're trying to get from point A to point B

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yeah

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multiplying numerator and denominator by something is the same as multiplying by 1

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well, if that thing isnt 0

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which we ignore

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because

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ignore™️

lyric vortexBOT
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@glacial storm

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