Question

Question below:

Answer 1

If \(\cos 2 \alpha=\dfrac{3\cos2 \beta-1}{3\cos 2 \beta}\) then \(\tan \alpha=?\)

Answer 2

@ganeshie8

Answer 3

@myininaya

Answer 4

use
the identity
(tan x)^2 = (1-cos2x)/(1+cos2x) and then proceed...

Answer 5

Let me see.

Answer 6

I got

\[\dfrac{1}{6 \cos 2\beta-1}\]

Answer 7

check your simplification

Answer 8

I am still getting the same answer.

Answer 9

Of course I will have to take square root to get tan alpha

Answer 10

@matricked ?

Answer 11

you can further
use thge identity
cos2y = (1- (tany)^2) / (1- (tany)^2) and proceed further...

Answer 12

So my simplification is right?

Answer 13

it seems...

Answer 14

Further simplification gives me:

\[\dfrac{\sec^2 \beta}{7-5\tan^2 \beta}\]

Answer 15

just take the root then ..

Answer 16

by the way can you recheck the question is somewhere 5 instead of a 3

Answer 17

\[a)\sqrt{2} \tan \beta \;\;b)\tan \beta \;\;c)\sin 2\beta \;\;d)\sqrt{2}\cot 2\beta\]

Answer 18

The question is right.

Answer 19

Shall i try my hand at solving this?

Answer 20

Yes?

Answer 21

sure help him...

Answer 22

Is any information given about Angles alpha and beta

Answer 23

Nope

Answer 24

Like they are acute or less than 90 greater than 90 ,acute (like these)

Answer 25

It must be given otherwise u can't proceed ahead!

Answer 26

??

Answer 27

not given

Answer 28

Check the heading of the question it must be or we have to assume things here

Answer 29

then assume alpha beta as acute angle

Answer 30

@OptimusPrime_
can you check the question once again...

Answer 31

it is right.

Answer 32

not about the question if any extra information is given check it seriously
@sidsiddhartha negative or positve acute angle

Answer 33

can you reveal the correct options...

Answer 34

its sqrt(2)

Answer 35

I will assume it is positive acute angles for answer sake!

Answer 36

if they are acute

Answer 37

No idea..qn is from a test I took today. I couldnt solve it during test.

Answer 38

I will help you! wait

Answer 39

If A and B are positive angles ( that's what i am assuming they must lie in the first Quadrant because theta is less than 90)

From this we can interpret that
sin A, cos A, tan A, tan B > 0

Answer 40

@OptimusPrime_
if you don't mind you are studying in which board

Answer 41

Sorry how is that relevant here?

Answer 42

\[\cos 2\alpha = 1 - 2\sin ^{2}\alpha \]

Answer 43

Are u familiar with that identity?

Answer 44

Yes. Proceed.