Show that the equation
2sec2x+4tan2x+10secx=02\sec^2 x + 4\tan^2 x + 10\sec x = 02sec2x+4tan2x+10secx=0
can be written in the form
asec2x+bsecx+c=0a\sec^2 x + b\sec x + c = 0asec2x+bsecx+c=0
where aaa, b b\,b and c c\,c are integers with a>0 a > 0\,a>0 and with no common factor other than 1.
Hence, given that x x\,x is obtuse, find the exact value of tanx\tan xtanx.
221 exam-style questions on CCEA A Level Maths 3.4 Trigonometry (A-level only), covering 3.4.1 Trigonometry (A-level only), 3.4.2 Trigonometry (A-level only), 3.4.3 Trigonometry (A-level only), 3.4.4 Trigonometry (A-level only), 3.4.5 Trigonometry (A-level only), 3.4.6 Trigonometry (A-level only), 3.4.7 Trigonometry (A-level only), and 3.4.8 Trigonometry (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.