# TrigonometryWatch

Thread starter 1 year ago
#1
Hi,
I'm trying to solve 3tanx=cosx but I'm getting the wrong answer. Apparently x should be 0.308 or 2.834. I'd be really grateful if someone could let me know what I'm doing wrong.
Here's what I did:
3sinx/cosx = cosx
3sinx = cos^2x
3sinx = 1-sin^2x
sin^2x + 3sinx - 1 = 0
sinx = 0.308 or sinx = -3.30
x = 17.9
Thanks
0
1 year ago
#2
Is one in radians and the other in degrees?
0.3 rad ~ 18 degrees
0
Thread starter 1 year ago
#3
(Original post by mqb2766)
Is one in radians and the other in degrees?
0.3 rad ~ 18 degrees
You're right, I forgot I needed to convert into radians. Thanks
0
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