Friday
March 24, 2017

Post a New Question

Posted by on Monday, June 11, 2012 at 5:03am.

How would I evaluate these trig functions without using a calculator? U:

sin(-13π/6)
cot 11π/6
cot(-14π/4)
sec 23π/6

Thanks in advance ^^; and if you'd tell me step by step on how to do problems like these I'd be grateful :D

  • Math/Trig - , Monday, June 11, 2012 at 11:29am

    sin(-θ) = -sinθ
    sin(θ±2kπ) = sinθ
    so, sin(-13π/6) = sin(-π/6) = -1/2

    tan(θ±kπ) = tanθ -- same for cot
    cot(11π/6) = cot(-π/6) = -cot(π/6) = -√3

    cot(-14π/4) = cot(2π/4) = cot(π/2) = 0

    sec(23π/6) = sec(-π/6) = √3/2

Answer This Question

First Name:
School Subject:
Answer:

Related Questions

More Related Questions

Post a New Question