Join your school's WhatsApp group
NECO June/July 2024 - Get offline past questions & answers - Download objective & theory, all in one app 48789

In the diagram above, O is the center of the circle. Calculate the length of...

Mathematics
WAEC 1989

In the diagram above, O is the center of the circle. Calculate the length of the chord AB if |OA| = 5cm, |OD| = 3cm and ∠AOD = ∠BOD

  • A. 3cm
  • B. 4cm
  • C. 5cm
  • D. 8cm
  • E. 15cm
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
NECO June/July 2024 - Get offline past questions & answers - Download objective & theory, all in one app 48789
Join your school's WhatsApp group
Correct Answer: Option D
Explanation

In \(\Delta DOB\), let < DOB = \(\alpha\)

In \(\Delta DOB\), \(5^2 = 3^2 + s^2\)

\(s^2 = 25 - 9 = 16\)

\(s = 4cm\)

\(\sin \alpha = \frac{4}{5}\)

\(\alpha = \frac{< AOB}{2}\)

Length of chord = \(2r \sin (\frac{\theta}{2})\)

|OB| = r = 5cm

L = \(2(5)(\frac{4}{5})\)

= 8 cm


Report an Error Ask A Question Download App
NECO June/July 2024 - Get offline past questions & answers - Download objective & theory, all in one app 48789
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
Join your school's WhatsApp group

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 }}
 
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
NECO June/July 2024 - Get offline past questions & answers - Download objective & theory, all in one app 48789
Join your school's WhatsApp group
Join your school's WhatsApp group
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
NECO June/July 2024 - Get offline past questions & answers - Download objective & theory, all in one app 48789