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# Trig watch

1. Show that tanx+ tan^-1x =tanx/sin^2x
What i DID WAS let tanx= sinx/cosx

but I'm stuck there
2. RDKGames

Put your degree to good use and help a brother out
3. I get really close by getting to
sinx/cosx + cosx/sinx
I get the sin^2 on the bottom but the top is wrong
4. (Original post by mariejuana)
I get really close by getting to
sinx/cosx + cosx/sinx
I get the sin^2 on the bottom but the top is wrong
sinx/cosx + cosx/sinx = (sin^2x + cos^2x)/sinxcosx by making both fractions have a common denominator.

The top =1 by identity.

Now divide top and bottom by cosx, then multiply top and bottom by sinx

5. Combine the fractions, then use sin(x)=sin^2(x)/sin(x) and you can get the tan and the sin^2 from that

god damnit why am I always late
6. (Original post by RDKGames)
sinx/cosx + cosx/sinx = (sin^2x + cos^2x)/sinxcosx by making both fractions have a common denominator.

The top =1 by identity.

Now divide top and bottom by cosx, then multiply top and bottom by sinx
I got 1/cosxsinx but I didn't think it was relevant to the question xD
7. (Original post by RDKGames)
sinx/cosx + cosx/sinx = (sin^2x + cos^2x)/sinxcosx by making both fractions have a common denominator.

The top =1 by identity.

Now divide top and bottom by cosx, then multiply top and bottom by sinx
That gives me sinx/sinxcos^2x what do I do now?
8. (Original post by mariejuana)
That gives me sinx/sinxcos^2x what do I do now?
From what I said, it should be (sinx/cosx)/sin^2x
9. (Original post by RDKGames)
From what I said, it should be (sinx/cosx)/sin^2x
When you say "top and bottom" do you mean the expression or to the numerator and the denominator
10. (Original post by mariejuana)
When you say "top and bottom" do you mean the expression or to the numerator and the denominator
By top and bottom I am referring to the numerator and denominator

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