Question

trigonometric functions

Answer 1

Well, you can start by testing a couple of values, to disprove it immediately
try A=30 and B=59

Tan30 + tan59 = tan89 ?

Answer 2

I for one, do not recall the tangent identity to be quite as simple as
tan(A) + tan(B) = tan(A + B)...

Answer 3

It's not @terenzreignz, but the question states for A+B< 90 which makes it not able to be an identity. But it's easy to disprove.

Answer 4

Why not
tan(45) + tan(30) = tan(75)
:)

Answer 5

tan 45 = 1. tan 22.5 <> .5

Answer 6

^that also disproves it, @highschoolmom2010

Answer 7

basically tana+tanb= (sinacosb+sinbcosa)/cosacosb= sin(a+b)/cosacosb

Answer 8

At least we have exact values for these stuff :3
\[\Large \tan(45^o) = 1\\\Large \tan(30^o)=\frac1{\sqrt{3}}\]

Answer 9

My reasoning for picking a A+B close to 90, was due to tan90 being undefined, so it's highly unlikely two smaller angles will give anything close to the tangent of an angle near 90

Answer 10

=(sinacosb+cosasinb)/cosacosb=/= sinasinb/cosacosb

Answer 11

Noted :)

Answer 12

Now i need to somehow prove sinacosb+sinbcosa=/=sinasinb...

Answer 13

@katherine.ok based on her other questions, I don't think she's at the level of trigonometry where they're using proofs. I think it's more an analytical question.

Answer 14

tan 60 + tan (-30) <> tan 30

Answer 15

I think as simple as this sound...

Answer 16

by using the tangent graph, adding a random point where x is (0,90),you will not get tan a+ tan b because it is not linear graph.

Answer 17

^ good point.

Answer 18

im lost on all of this tbh....