## Additional Math – Trigonometry – The most challenging question we came across – mid year 2019 Exam

While preparing students for the mid year exam 2019, I stumbled upon a very challenging question, I have never came [...]

By |2019-05-16T13:06:55+08:00May 16th, 2019|A-Math - Trigonometry|

## Additional Math – Differentiation – Equations with cot x and cosec x

$latex \displaystyle y={{\cot }^{2}}x-5+\cos ecx$ It is difficult to differentiate cot x and cosec x directly. You need to change [...]

By |2018-12-23T11:26:43+08:00December 23rd, 2018|A-Math - Differentiation, A-Math - Trigonometry|

## Additional Math – Trigonometry – Prove Identities of (tan x-1)/(tan x+1)

RHS $latex \displaystyle \frac{{\tan x-1}}{{\tan x+1}}$ Change tan x  to sin x /cos x  and 1 to cos x /cos [...]

By |2018-09-14T11:24:29+08:00September 14th, 2018|A-Math - Trigonometry|

## Additional Math – Trigonometry – Prove the Identity Cos x/ (1- Sin x) = Tan x + Sec x

$latex \displaystyle \frac{{\cos x}}{{1-\sin x}}=\tan x + \sec x$ The rule of thumb is to always prove from the side [...]

By |2018-07-09T11:01:24+08:00June 20th, 2018|A-Math - Trigonometry|

Use the Cosine Double Angle Formula (found in Formula List) to help derive Cosine 1/2 Angle. $latex \displaystyle \text{cos}\ 2A=2{{\cos [...] By |2018-01-09T04:19:42+08:00January 3rd, 2018|A-Math - Trigonometry| ## Additional Math – Trigonometry – Using the R-Formula to Change a Trigonometric Expression$latex \displaystyle 10{{\cos }^{2}}x+4{{\sin }^{2}}x+8\sin x\cos x$Split 10 cos2x and factorize 8sinxcosx.$latex \displaystyle 6{{\cos }^{2}}x+4{{\cos }^{2}}x+4{{\sin [...]

By |2017-11-17T07:33:29+08:00July 3rd, 2017|A-Math - Trigonometry|

## Additional Math – Trigonometry – Sketch the Graphs and Find the Number of Solutions

Sunday 12 Noon Additional Math Tuition Class. - Sketching of Cosine Graph and a Linear graph.     [...]

By |2017-11-17T07:43:58+08:00June 8th, 2017|A-Math - Trigonometry|