SOLUTION: If cos=-4/5 in quadrant II, what is Sin, Tan, Csc, Cot, and Sec?

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Question 1071269: If cos=-4/5 in quadrant II, what is Sin, Tan, Csc, Cot, and Sec?
Answer by ikleyn(52824) About Me  (Show Source):
You can put this solution on YOUR website!
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Then  sin(x) = sqrt%281+-+cos%5E2%28x%29%29 = %281+-+%28-4%2F5%29%5E2%29 = sqrt%281+-+16%2F25%29 = sqrt%28%2825-16%29%2F25%29 = sqrt%289%2F25%29 = 3%2F5.

The sign at sqrt is "+" since sine is positive in QII.


tan = sin/cos,

csc = 1/sin,

cot = cos/sin,

sec = 1/cos.

For many other similar solved problems see the lessons
    - Calculating trigonometric functions of angles
    - Advanced problems on calculating trigonometric functions of angles
in this site.

They are the part of the online textbook
    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.
under the topic "Trigonometry: Solved problems".