Question

find the
signs of
a) cot (-206] °​

Answer 1

We have:

$\cot (-206)$°

We have to find, the sigh of $\cot (-206)$° is:

Solution:

∴ $\cot (-206)$°

Using identity:

$\cot (-A)$ = - $\cot (A)$

= - $\cot (206)$°

= - $\cot (180+26)$°

Using identity:

$\cot (180+A)$ = $\cot (A)$

= - $\cot 16$ °

∴ The sign of $\cot (-206)$° = negative(- ).

Thus, the sign of $\cot (-206)$° is "negative(- )".

Answer 2

Given:

Cot[-206]°

To find:

The sign for the given trigonometry.

Solution:

The sign convention for the cot ratio of the trigonometry is given by:

Cot[-A] = -Cot A

For any angle A.

And the Sign convention of the trigonometry is given by:

Quadrant                Positive Ratio

First                          All Ratio

Second                    Sin and Cos

Third                         Tan and Cot

Forth                         Sec and Cosec

So,

Cot[-206]°

-Cot[206]°

-Cot[180+26]°

Means in the third quadrant where Cot is Positive

-Cot[180+26]° = -Cot[26]°

Hence,

Sign of Cot[-206]°  is negative.