Can someone tell me the solution of following problems:
1.
My solution sinx/2
2.
I have to get other 2 values
sinx=2/3
_______
sin2x = ?
tan(pi/4-x) = ?
3.
y = x/5 - 1
y = -5x/4 + 1
k1 = 1/5
k2 = -5/4
1.) Yes, assuming that you are supposed to simplify that expression, I'm also arriving at .
2.) Hmm, I think there's some information missing here. In order to evaluate , you could use the identity . Since you have the value of , can be found using - but that gives two values for , one positive and another negative. Usually, these type of questions will give a rage for the value of x, or make a comment such as "x is an acute angle", so that you can determine whether is positive or negative.
3.) Please be clearer. Specifically, makes literally no sense.
2.) Lets say it is positive. For cosx I get square root of 5 divided by 3. For tanx I get 2 times square root of 5 divided by 5.
Now I put this values to get sin2x (my solution is 4 times square root of 5 divided by 9) and to get tan(pi/4 - x), my solution to this is 1 - (2 times square root of 5 divided by 5) / 1 + (2 times square root of 5 divided by 5)
3.) I ment tanφ
and my solution is: 62° 39'
Thank you very much.