Question

what is the exact value of tan15

Answer 1

tan(A−B) = (tan A − tan B) / (1 + tan A tan B)

Answer 2

Tan(45 - 15)

Answer 3

OOPS Tan(45 - 30)

Answer 4

(tan 45 - tan 30)/(1 + tan45*tan30)

Answer 5

Tan 45 = 1
tan 30 = sqrt3/3

Answer 6

(1 - sqrt3/3)(1 + sqrt3/3)

Answer 7

how do you simplify that? the answer is supposed to be 2 - sqrt3

Answer 8

Just a minute... I don't get that answer.. Let me go back thru my math

Answer 9

i got up to where you got before too

Answer 10

OK

(1 = sqrt3/3) / (1 + sqrt3/3)

Answer 11

Now you multiply by the conjugate which is (1 - sqrt3/3)/(1-sqrt3/3)

Answer 12

(1 - sqrt3/3)(1 - sqrt3/3)

---------------------
(1 + sqrt3/3)(1 - sqrt3/3)

Answer 13

1 - sqrt3/3 - sqrt3/3 + 3/9
------------------------
1 - 3/9

Answer 14

1 - 2sqrt3/3 + 1/3
-----------------
2/3

Answer 15

4/3 - 2sqrt3/3
-------------
2/3

Answer 16

(4 - 2sqrt3)/3 divided by 2/3


(4 - 2sqrt3)/3 times 3/2

Answer 17

The threes would cancel

(4 - 2sqrt3)/2

Answer 18

divide the 2 into each term

2 - sqrt3

Answer 19

how do you find the conjugate again?

Answer 20

The conjugate is basically the denominator but take the opposite sign
ex. denominator = 1 - sqrt5 conjugate 1+sqrt5/1+sqrt5

Answer 21

perfect, thanks!

Answer 22

UR welcome

Answer 23

hey, you could use this http://web2.0calc.com/