I am 14 years old and I couldn't solve this trigonometry question, if tan2x=3/4 then what is the value of sinx?

Question

owlfred · Answer

Hoot! You just asked your first question! Hang tight while I find people to answer it for you. You can thank people who give you good answers by clicking the 'Good Answer' button on the right!

anonymous · Answer

Tan 2x = 3/4 = .75
 2x     =   arc tan(.75) = 36.87 degrees
   x= 36.87/2  = 18.44 degree
sinx= sin 18.44 = 0.31622   use calculator

anonymous · Answer

did u get the process of doing it korcan?

anonymous · Answer

well thanky you , but I found the answer as sinx= 1/3√5, and whats the meaning of arc?

anonymous · Answer

I don2T know if my answer is true.

anonymous · Answer

14yrs old?

anonymous · Answer

that makes you like yr9 , this is a yr11/12 question

anonymous · Answer

mark o. you did it wrong , they want an exact value for it

anonymous · Answer

you need to use double angle expansion

anonymous · Answer

YEa i am 14 years old and i learned trgionometry and function when i was 12 ^^

anonymous · Answer

$$\tan(2x) = \frac{2\tan(x)}{1-\tan^2(x)} $$

anonymous · Answer

mhmh just have a look at my answer mybe?

anonymous · Answer

and check it please?

anonymous · Answer

well u need to put the answer right awy so that we know tht u want to arrive at the answer w/c is 1/3sqrt5.....lol

anonymous · Answer

1/(3sqrt5) = 0.316227766 using a calculator... does your teacher allow you to use calculator? ...lol...

anonymous · Answer

you need to use a scientific calculator in order to solve trig, sometimes calculator serves you to check if your answer is correct....

anonymous · Answer

im sure you can use a table of trig fuctions?..lol

anonymous · Answer

arctangent is like this:
  
 tan(36.87deg)=3/4   now the reverse of it is....

         36.87deg=arc tan(3/4)

             or arc tan(3/4) = 36.87deg

anonymous · Answer

did you get it korcan?

anonymous · Answer

you can ask question if you are not sure so that we can explain to you better..lol

anonymous · Answer

OKA i got it thank you ^^but my teacher doesn2T let me use calculater, :( or table of trig fuctions :( but i know how to use it ^^

anonymous · Answer

and i also dun have a calculator at hause xd ^^ and dun have calculator on p ctoo but i can program a calculator when i need ^^