Trig: Find all solns of 4 sin % - 3 = 0 between 0, 360 degre

[hotlajake]

i need help understanding this problem.
datum = %

find all solution between 0 degrees and 360 degrees.
4 sin % -3 = 0

i went from that to this

sin % = -3/4

Now when i plus this in I get -.013

i am suppose to get 48.6 and 131.4 (both degrees) how is this done? steps would be great and why...

 

[tkhunny]

Re: Trig

i need help understanding this problem.
sin % = -3/4

1) 4sin(x) - 3 = 0 leads to sin(x) = +3/4. That will help.

2) Your calculator is set to Radians. Set it to degrees if you want degrees.

3) You should be acquainted with the Unit Circle. This will help you find the second value. Your calculator should give you only one value.

 

[masters]

TK corrected your equation to be sin(x) = 3/4 instead of sin(x) = -3/4


If you know the ratio and are trying to determine the angle, you must use the inverse sin (sin[sup:2mn56dna]-1[/sup:2mn56dna]) of the ratio.

We ask the question "What angle has a sin ratio of 3/4?

If sin(x) = 3/4, then sin[sup:2mn56dna]-1[/sup:2mn56dna](3/4) = 48.6. The sin ratio is positive in Quad 1 and Quad 2, so 180 - 48.6 = 131.4 is your other angle.