Introduction to...

$$cot\, \angle DBA$$ 

If  $$ \tan A + \cot A = 5$$; find the value if $$\tan^{2}\, A\, +\, \cot ^{2} A$$.

$$\displaystyle \frac {1}{x^2}+\frac {1}{y^2}$$ is equal to

If $$3 \sin\theta+ 5 \cos\theta=5$$, then $$5 \sin\theta-3 \cos\theta$$ is equal to

$$\displaystyle \left (\frac{\sin\, 50^{\circ}}{\cos\, 40^{\circ}} \right)^{2}\, +\, \left (\frac{\cos\, 28^{\circ}}{\sin\, 62^{\circ}} \right)^{2}\, -\, 2\, \tan^{2}\, 45^{\circ}$$

If $$x^2\tan^260^o-4x \cos^2 45^o=4 \sin 30^o \cos 60^o \tan 45^o$$ and $$x$$ is not an integer then $$x$$ is equal to:

If $$tan\, x^{\circ}\, =\, \dfrac{5}{12},\, tan\, y^{\circ}\, =\, \dfrac{3}{4}$$ and $$AB = 48 m$$; find the length of $$CD$$.

If $$\sin A = \displaystyle\frac{3}{4}$$, calculate $$\cos A$$ and $$\tan A$$.

Evaluate
$$(i)\quad \sin60^{\small\circ}\cos30^{\small\circ}+\sin30^{\small\circ}\cos60^{\small\circ}$$

$$(ii)\quad \displaystyle\frac{5\cos^260^{\small\circ}+4\sec^230^{\small\circ}-\tan^245^{\small\circ}}{\sin^230^{\small\circ}+\cos^230^{\small\circ}}$$

If, $$\displaystyle \tan \, 9^o = \frac{x}{y}$$ then, value of $$\displaystyle \frac{\sec^2\, 81^o}{1+\cot^2\, 81^o}$$ is