Question

Find the exact value of cot7pi/4

Answer 1

Answer:

-1

Step-by-step explanation:

The radian gives the coordinates: ($(\sqrt{2 } /2,-\sqrt{2 } /2)$ (found using the unit circle)

cot=x/y

Plug the x and y coordinates into their respective places in the equation.

You get the answer of -1.

Answer 2

Answer:

-1

Step-by-step explanation:

Use a unit circle to find "exact" values.

On the unit circle, first find your angle, 7pi/4. Its a big angle, 315° that's trivia right now though.

Then look at the coordinates of the point at 7pi/4. They are:

(root/2, -root2/2) See image.

sin is the y coordinate. cos is the x coordinate. tangent is y/x.

cotangent is the reciprocal of tangent. This means to find cotangent, flip over tangent.

cotangent is x/y.

cot 7pi/4 =

(root2/2)over(-root2/2)

= -1