Which expression is equivalent to (2x + 4)2 − (2x2 + 6)?
a) 2x2 + 16x − 2
b) 2x2 + 16x + 10
c) 4x2 + 16x + 10
d) 4x2 + 16x − 2

The trigonometric ratios sine and secant are reciprocals of each other

What is the greatest number of parts of a circle that can be formed by cutting the circle with 7 straight cuts? (note: the parts do not have to be equal in size)

If value of cos330° is √3/2 then find tan165°.