find exact value without a calculator:
cot(3pi/4)

Question

find exact value without a calculator:
cot(3pi/4)

debbieg · Answer

Welcome to Open Study! :)

Do you understand how to use a reference angle and the quadrant location to find trig function values for multiples of the "common angles", pi/3 (60*), pi/4 (45*), and pi/6 (30*)?

debbieg · Answer

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debbieg · Answer

The function values for an angle differ from the function value for its reference angle, if at all, only in their SIGN. Since this is Q2 you know that cotangent is negative.

So  cot(3pi/4)=-cot(reference angle)

anonymous · Answer

Hi,

I believe the exact value will be -1. I have my reasoning if you are interested.

Remember OpenStudy is here for you. Have a great night!
~Chance~

anonymous · Answer

$$\cot \frac{ 3\pi }{ 4 }=\cot \left( \pi-\frac{ \pi }{4 } \right)=-\cot \frac{ \pi }{ 4 }=-1$$

anonymous · Answer

$$\cot \frac{ 3\pi }{4 }=\cot \left( \frac{ \pi }{2 }+\frac{ \pi }{4}\right)=-\tan \frac{ \pi }{4 }=-1$$

goformit100 · Answer

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