Without a calculator, sec^2 20^circ - tan^2 20^circ =

  1. 1
  2. 0
  3. 2
  4. sec 40^circ
Answer

A) 1

sec^2theta - tan^2theta = 1 for every angle. SLO M-09-B-24 · Application

Mathematics MCQ · More Trigonometric Identities MCQs · Practise