Question

if csc theta=-5/3 and theta has its terminal side in quadrant 3, find the exact value of tan 2 theta

Answer 1

\[\tan 2x=\frac{ 2tanx }{ 1-\tan^2x }\]

Answer 2

\[sinx=\frac{ -3 }{ 5 }\]

Answer 3

now get the value of tan x and substitute in my formula

Answer 4

@mustafa2014 \[\csc x=\frac{ 1 }{ \sin x }\]

Answer 5

yep :)

Answer 6

how do you find the value of tan x?

Answer 7

\[tanx=\frac{ \sin x }{ \cos x }\]

Answer 8

\[\cos x=\frac{ -4 }{ 5 }\]

Answer 9

so tan x= 3/4 right?

Answer 10

right

Answer 11

so 279.5º?

Answer 12

the angle should be between 180 and 270

Answer 13

217 degrees approx.

Answer 14

I must of done my math wrong then. I plugged in 3/4. so 2tan(3/4)/1-tan^2(3/4) which was 1.8/0.36= 4.87* 180/π. what did i do wrong?

Answer 15

tan 2x=24/7

Answer 16

just substitute the value of tanx=3/4 in the formula i gave in the beginning!

Answer 17

oh ok, I see. Thank you for your help again!