Question

Evalute w/o using a calulator!
csc(-420)
Please explain & show work because i'm very new to this!

Answer 1

find reference angle
take away 360 since that is one time around unit circle
csc(-60) you are 60 degrees away from axis in 4th quandrant (csc is neg)

csc x = 1/sinx
--> sin(60) = sqrt3/2

--> csc(60) = 2/sqrt3

finally make it neg because you are in 4th quadrant
-2/sqrt3

Answer 2

no wait. csc(x) = 1/sin(x)

and sin(-60)= -sqrt(3)/2
so -2/sqrt(3) or -2 sqrt(3)/3

sure and steady (like dumbcow) is the best way...

Answer 3

But you should memorize cos(60) = 1/2 sin(60)= sqrt(3)/2 tan(60)= sqrt(3)

Answer 4

thank you:)