Geometry
Sum and Difference Trigonometric Formulas
If \(\sin\theta= \cos\theta\), find the value of \(\cos 2\theta\).
by
Parth Lohomi
If \(A + B = 225^{\circ}\), find \((1+\tan A)(1+\tan B),\) where defined.
by
Omkar Kulkarni
\[\large \frac {1}{\cos 80^\circ } - \frac {\sqrt 3}{\sin 80^\circ } = \ ? \]
Hint: How can we write the numerators in relation to common trig values?
by
Gagan Raj
If \[\cos\left[6\arccos \left(\dfrac{1}{3}\right)\right] = \frac{A}{B},\] where \(A\) and \(B\) are relatively prime positive integers, find \(B-A.\)
by
Pratik Shastri
\[ \sin^2 18^ \circ + \sin ^2 30 ^ \circ. \]
Which of the following is equal to the above expression?
by
Calvin Lin