If cot A = $\left[\frac{sin B}{(1 - cos B)}\right]$, then what is the value of cot 2A?
1). cot($\frac{B}{2}$)
2). cot 2B
3). cot B
4). tan B
What is the value of $\frac{3}{2}\left(\frac{cos 39^{0}}{sin 51^{0}}\right)-\sqrt{sin^{2}39^{0}+sin^{2}51^{0}} $
1). $\frac{1}{2}$
2). $\frac{5}{2}$
3). 0
4). both $\frac{1}{2}$ and $\frac{5}{2}$
If $cosec2 \theta$ = $\frac{635}{576}$, then what is the value of $\left[\frac{(sin \theta - cos \theta)}{(sin \theta + cos \theta)}\right]$?
1). 1
2). $\frac{31}{17}$
3). $\frac{17}{31}$
4). $\frac{14}{25}$
PQ is a diameter of a circle with centre O. RS is a chord parallel to PQ subtends an angle of $40^{0}$ at the centre of the circle. If PR and QS are produced tomeet at T, then what will be the measure (in degrees) of $\angle PTQ$?
1). 55
2). 60
3). 70
4). 90
If $x - \frac{1}{x}$ =1, then what is the value of $\frac{1}{x}\left(\frac{1}{x-1}-\frac{1}{x+1}+\frac{1}{x^{2}-1}-\frac{1}{x^{2}+1}\right)$
1). $\pm \sqrt{5}$
2). $\frac{2}{5}$
3). $\pm \frac{2}{\sqrt{5}}$
4). $\pm \frac{\sqrt{5}}{2}$