Question

Can anybody help me with basic trigonometric identities and how to solve problems, I Have to be done by tonight so I can graduate on Saturday.

Answer 1

do u have a specific question ?

Answer 2

yes i do hold on one sec

Answer 3

Problem 3: Given tan x=13 and cos x<0, find the value of sin x.

Answer 4

well the tan x = 1/3

Answer 5

okay :)

Answer 6

cosx < 0

that means `cos` is negative, right ?

Answer 7

yes

Answer 8

in which quadrants is the `cos` negative ?

Answer 9

https://encrypted-tbn2.gstatic.com/images?q=tbn:ANd9GcSkoSG9ym_CyxW4utbDnbDDxyFXaQcfZSVB2Z3PtYnmUd_WfR6R

Answer 10

i honestly dont know

Answer 11

oh thanks i see

Answer 12

good, so which quadrants is the `cos` negative ?

Answer 13

seems to be 2 and 3 where the cos is -

Answer 14

You got it !

Answer 15

thanks

Answer 16

and since the tan = 1/3 is positive, the ray must lie in 3rd quadrant.

Answer 17

alright i see

Answer 18

So thats the reference triangle in IIIrd quadrant,
can u find the missing hypotenuse side ?

Answer 19

the hyp would be 10?

Answer 20

dont forget the sqrt

Answer 21

hypotenuse = \(\large \sqrt{10}\)

Answer 22

oh yea