Question

Given that sec 3π/10 ≈ 17/10 and csc 3π/10 ≈ 17/14, find the following:
1. sin 3π/10 ≈ 14/17 (is this one correct)
2. csc 43π/10 ≈
3. sec 2π/10 ≈
4. cot -12π/10 ≈
5. tan π/5 ≈
6. sin -7π/10 ≈
7. cos 13π/10 ≈
8. tan -33π/10 ≈

i don't understand how to do the others can someone please explain?

Answer 1

Didn't we just do one of these?

sec 3π/10 = 17/10, csc 3π/10 = 17/14 means
r=17
x=10
y=14

csc 43π/10 = csc(4π + 3π/10) = csc 3π/10
sec 2π/10 = sec(π/2 - 3π/10) = csc 3π/10
cot -12π/10 = -cot 12π/10 = -cot(π+2π/10) = -cot 2π/10 = -tan 3π/10

Try the others. Recall the basic definitions of the trig functions in terms of x,y,r.