SOLUTION: if cos x = squareroot of 2 over 2 in which quadrants could angle x terminate only one 2 has the square root

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Question 906371: if cos x = squareroot of 2 over 2 in which quadrants could angle x terminate only one 2 has the square root
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
if cos x = squareroot of 2 over 2 in which quadrants could angle x terminate only one 2 has the square root
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Note: sqrt(2)/2 is a positive number.
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By devinition, cosine = x/r
r is always positive because r = sqrt(x^2+y^2)
So cos is positive when x is positive.
x is positive in QI and in QIV
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Ans: the angle must terminate in QI or in QIV.
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Cheers,
Stan H.
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