JAMB CBT Mobile App 2025 - Free Download
JAMB CBT Software 2025 - Free Download

Given that cos z = L , whrere z is an acute angle, find an...

Mathematics
JAMB 1983

Given that cos z = L , whrere z is an acute angle, find an expression for \(\frac{\cot z - \csc z}{\sec z + \tan z}\)

  • A. \(\frac{1 - L}{1 + L}\)
  • B. \(\frac{L^2 \sqrt{3}}{1 + L}\)
  • C. \(\frac{1 + L^3}{L^2}\)
  • D. \(\frac{L(L - 1)}{1 - L + 1 \sqrt{1 - L^2}}\)
JAMB CBT Software 2025 - Free Download
JAMB CBT Mobile App 2025 - Free Download
JAMB CBT 2025 - Candidates, Schools, Centres, Resellers - Get Ready!
WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076
Correct Answer: Option D
Explanation

Given Cos z = L, z is an acute angle

\(\frac{\text{cot z - cosec z}}{\text{sec z + tan z}}\) = cos z

= \(\frac{\text{cos z}}{\text{sin z}}\)

cosec z = \(\frac{1}{\text{sin z}}\)

cot z - cosec z = \(\frac{\text{cos z}}{\text{sin z}}\) - \(\frac{1}{\text{sin z}}\)

cot z - cosec z = \(\frac{L - 1}{\text{sin z}}\)

sec z = \(\frac{1}{\text{cos z}}\)

tan z = \(\frac{\text{sin z}}{\text{cos z}}\)

sec z = \(\frac{1}{\text{cos z}}\) + \(\frac{\text{sin z}}{\text{cos z}}\)

= \(\frac{1}{l}\) + \(\frac{\text{sin z}}{L}\)

the original eqn. becomes

\(\frac{\text{cot z - cosec z}}{\text{sec z + tan z}}\) = \(\frac{L - \frac{1}{\text{sin z}}}{1 + sin \frac{z}{L}}\)

= \(\frac{L(L - 1)}{\text{sin z}(1 + \text{sin z})}\)

= \(\frac{L(L - 1)}{\text{sin z} + 1 - cos^2 z}\)

= sin z + 1

= 1 + \(\sqrt{1 - L^2}\)

= \(\frac{L(L - 1)}{1 - L + 1 \sqrt{1 - L^2}}\)


Report an Error Ask A Question Download App
JAMB CBT Software 2025 - Free Download
JAMB CBT 2025 - Candidates, Schools, Centres, Resellers - Get Ready!
JAMB CBT Mobile App 2025 - Free Download
WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076

Contributions ({{ comment_count }})

Please wait...

{{ settings.no_comment_msg ? settings.no_comment_msg : 'There are no comments' }}

Quick Questions

Post your Contribution

Please don't post or ask to join a "Group" or "Whatsapp Group" as a comment. It will be deleted. To join or start a group, please click here

{{ quote.posted_by.display_name }}
{{ settings.form_textarea_description }}
 
JAMB CBT Software 2025 - Free Download
WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076
JAMB CBT 2025 - Candidates, Schools, Centres, Resellers - Get Ready!
JAMB CBT Mobile App 2025 - Free Download
JAMB CBT Software 2025 - Free Download
WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076
JAMB CBT 2025 - Candidates, Schools, Centres, Resellers - Get Ready!
JAMB CBT Mobile App 2025 - Free Download