I would imagine it would go something like thisHello, and welcome to FMH!
If \(\cos(\theta)=0.85\), this means \(\theta\) is either a quadrant I or quadrant IV angle (since we're given no other information about \(\theta\)). I would indeed begin with a Pythagorean identity:
[MATH]\sin^2(\theta)+\cos^2(\theta)=1[/MATH]
Can you solve this for \(\sin(\theta)\)?
First of all sin has no meaning so saying sin=0.2775 is meaningless. You compute sin of angles, like sin 70o, sin 125oand sin 7radians.I would imagine it would go something like this
sin2(θ)+cos2(0.85)=1
sin2(θ)=1-0.7225=0.2775
sin=0.2775
however this does not coincide with the answer that is given at the back of my math book and the fast reply and welcome is much appreciated!
That can't be the correct answer, because it equals 1.1547, and sines and cosines can't be greater than 1! Check that you looked at the answer to the right problem.I understand that I am suppose to use the pythagoras theorem, but i am not sure how.
The answer that i am suppose to arrive at is below. Thanks!
2√3
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3