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Trig

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

but I'm stuck there
@RDKGames


Put your degree to good use and help a brother out :biggrin:
(edited 6 years ago)
Reply 2
Avatar for mariejuana
mariejuana
OP
10
I get really close by getting to
sinx/cosx + cosx/sinx
I then made cosx= sinx/tanx
I get the sin^2 on the bottom but the top is wrong
Original post by mariejuana
I get really close by getting to
sinx/cosx + cosx/sinx
I then made cosx= sinx/tanx
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
sin(x)cos(x)+cos(x)sin(x)=sin(x)sin(x)cos(x)sin(x)+cos(x)cos(x))sin(x)cos(x)\frac{sin(x)}{cos(x)}+\frac{cos(x)}{sin(x)}=\frac{sin(x)sin(x)}{cos(x)sin(x)}+\frac{cos(x)cos(x))}{sin(x)cos(x)}
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
(edited 6 years ago)
Reply 5
Avatar for mariejuana
mariejuana
OP
10
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
Reply 6
Avatar for mariejuana
mariejuana
OP
10
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?
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
Reply 8
Avatar for mariejuana
mariejuana
OP
10
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
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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