JAMB CBT 2025 - Candidates, Schools, Centres, Resellers - Get Ready!
JAMB CBT Software 2025 - Free Download

2024 WAEC Further Mathematics Theory If tan x = \(\frac{1}{3}\), where 180º < x < 270º evaluate \(\frac{sin2 x - cos...

Further Mathematics
WAEC 2024

If tan x = \(\frac{1}{3}\), where 180º < x < 270º

evaluate \(\frac{sin2 x - cos x}{2 tan x + sin 2x}\), leaving the answer in surd form (radicals)

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
Explanation

hyp\(^2\) = 3\(^2\) + 1\(^2\) (Pythagoras's theorem)

hyp = \(\sqrt{10}\)

Given: tan x =  \(\frac{1}{3}\) ( sin and cos will be in the third quadrant and are both negative where 180º < x < 270º)

sin x =  \(\frac{-1}{\sqrt{10}}\), cos x = \(\frac{-3}{\sqrt{10}}\)

\(\frac{sin2 x - cos x}{2 tan x + sin 2x}\) =  \(\frac{2sinx cos x - cos x}{2 tan x + 2sin x cos x}\) but 2snx cox = \(\frac{3}{5}\)

\(\frac{sin2 x - cos x}{2 tan x + sin 2x}\) = \(\frac{\frac{3}{5} + \frac{3}{\sqrt{10}}}{2(\frac{1}{3}) + \frac{3}{5}}\) = \(\frac{\frac{3}{5} + \frac{3}{\sqrt{10}}}{\frac{19}{15}}\)

= (\(\frac{3}{5}\) + \(\frac{3\sqrt{10}}{10}\)) \(\div\) \(\frac{19}{15}\) = \(\frac{15}{19}\)[\(\frac{3}{5}\) + \(\frac{3}{\sqrt{10}}\)]

= \(\frac{9}{19}\) + \(\frac{45}{19\sqrt{10}}\)

= \(\frac{9}{19}\) + \(\frac{45 \sqrt{10}}{19(10)}\)

= \(\frac{9}{19}\) + \(\frac{9 \sqrt{10}}{19(2)}\)

= \(\frac{9}{19}\)[1 + \(\frac{\sqrt{10}}{2}\)]


Report an Error Ask A Question Download App
JAMB CBT Mobile App 2025 - Free Download
JAMB CBT Software 2025 - Free Download
JAMB CBT 2025 - Candidates, Schools, Centres, Resellers - Get Ready!
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 Mobile App 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 Software 2025 - Free Download
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