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June 22, 2025, 06:06:17 am

Author Topic: Calc 1 Trig Substitution  (Read 776 times)  Share 

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VivaTequila

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Calc 1 Trig Substitution
« on: June 02, 2012, 04:18:37 pm »
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Asked to simplify: Cos^2(x)/sin(x) + sin(x)
Answer is cosec^2(x)

I understand that if you divide both terms by sin(x), you get:
cot(x)+1

which is equivalent to cosec^2(x)

but why is it that when you multiply both terms by sin(x), you get cos^2(x)+sin^2(x), which is 1, which is not cosec^2(x) - the answer...

cheers

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Re: Calc 1 Trig Substitution
« Reply #1 on: June 02, 2012, 04:27:07 pm »
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Are you sure is the answer?
Wouldn't it just be ?



I understand that if you divide both terms by sin(x), you get:
cot(x)+1

which is equivalent to cosec^2(x)
Also note that when you divide by sin(x), that , it's


Also just to make sure I'm not seeing things, http://www.wolframalpha.com/input/?i=cos%5E2(x)%2Fsin(x)%2Bsin(x)&t=crmtb01

So the answer is not
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VivaTequila

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Re: Calc 1 Trig Substitution
« Reply #2 on: June 02, 2012, 05:00:09 pm »
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right you are, thanks for the speedy reply!

and hmm...

why is it that the sin(x) doesn't cancel out?