Question

How do you find the value of `csc ((-3pi)/4)`?

Answer 1

Note `pi=180^circ`

`csc ((-3pi)/4) = 1/sin((-3pi)/4)`

On the trig unit circle:

`sin ((-3pi)/4) = - sin ((pi)/4) =-sin(180^circ/4)=-sin(45^circ)= -sqrt2/2`

`csc ((-3pi)/4) = -2/sqrt2 = -sqrt2`