1. ## Cofunction identities

3. Use the cofunction identities to write an expression that is equivalent to each of the following expressions.

Tan 3/8

3(180)/8= 67.5

=cot (/2-67.5)
=cot 22.5 22.5 x /180
= cot /4

the answer is cot /8 I dont know why though..

2. Originally Posted by Skoz
3. Use the cofunction identities to write an expression that is equivalent to each of the following expressions.

Tan 3/8

3(180)/8= 67.5

=cot (/2-67.5)
=cot 22.5 22.5 x /180
= cot /4

the answer is cot /8 I dont know why though..
co-function identities ...

$\sin(x) = \cos\left(\frac{\pi}{2} - x\right)$

$\tan(x) = \cot\left(\frac{\pi}{2} - x\right)$

$\sec(x) = \csc\left(\frac{\pi}{2} - x\right)$

now ... what is $\frac{\pi}{2} - \frac{3\pi}{8}$ ?