How to find the value of csc ((3pi)/4)csc(3π4)?

1 Answer
Jun 5, 2015

The angle ((3pi)/4)(3π4) is in Quadrant 2 with a reference angle of pi/4π4

sin(pi/4) = 1/sqrt(2)sin(π4)=12color(white)("XXXX")XXXX(it's one of the standard angles)

and in Quadrant 2, sin(x)sin(x) is positive, so
color(white)("XXXX")XXXXsin((3pi)/4) = sin(pi/4) = 1/sqrt(2)sin(3π4)=sin(π4)=12

csc(x) = 1/(sin(x))csc(x)=1sin(x)

So
csc((3pi)/4) = sqrt(2)csc(3π4)=2