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If cos0=1/4 what is the value os in 0? Assume that 0 is an angle in the first quadrant
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The formulation has typos.
Let me reformulate (and solve) it as it should be.
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If = what is the value of ?
Assume that is an angle in the first quadrant.
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Solution
If = then = = = = = = .
The sign "+" was chosen at the square root because the sine is positive for an angle at the first quadrant.