## Ratio and probability problem

It is always assumed that a sample has all the characteristics of the population from which it is taken. For example, if it is given that the ratio of men to women in a population is 2:3 or 40% to 60%, the same will be true to the sample. Problem A survey has shown that

## Trigonometric equations and their graphs

The general technique in matching trigonometric graphs and equations is to consider the intercepts, the minimum and maximum points, the shape of the prototype graph and the transformations done to the graph. Problem If 0≤x≤2π which one of the following trigonometric equations best describes this graph? A. y = 3cos 2x B. y = 2+cos

## Proving trigonometric identities #1

The common error in proving trigonometric identities is to assume the equality of the left-hand side (LHS) and the right-hand side (RHS) of what is being proved. To prove an identity means to transform the LHS and RHS in the same form. Prove the identity: Solution sure to get 0/5 mark: This is a ratio