Rewriting a trigonometric expression using the difference of squares
Rewrite the trigonometric expression:
Notice that both the coefficient and the trigonometric expression in the first term are squared, and the square of the number 1 is 1. This is the difference of squares. Thus,
There are multiple ways to represent a trigonometric expression. Verifying the identities illustrates how expressions can be rewritten to simplify a problem.
Graphing both sides of an identity will verify it. See
[link] .
Simplifying one side of the equation to equal the other side is another method for verifying an identity. See
[link] and
[link] .
The approach to verifying an identity depends on the nature of the identity. It is often useful to begin on the more complex side of the equation. See
[link] .
We can create an identity by simplifying an expression and then verifying it. See
[link] .
Verifying an identity may involve algebra with the fundamental identities. See
[link] and
[link] .
Algebraic techniques can be used to simplify trigonometric expressions. We use algebraic techniques throughout this text, as they consist of the fundamental rules of mathematics. See
[link] ,
[link] , and
[link] .
Section exercises
Verbal
We know
is an even function, and
and
are odd functions. What about
and
Are they even, odd, or neither? Why?
Step 1: Find the mean. To find the mean, add up all the scores, then divide them by the number of scores. ...
Step 2: Find each score's deviation from the mean. ...
Step 3: Square each deviation from the mean. ...
Step 4: Find the sum of squares. ...
Step 5: Divide the sum of squares by n – 1 or N.
The sample of 16 students is taken. The average age in the sample was 22 years with astandard deviation of 6 years. Construct a 95% confidence interval for the age of the population.
Bhartdarshan' is an internet-based travel agency wherein customer can see videos of the cities they plant to visit. The number of hits daily is a normally distributed random variable with a mean of 10,000 and a standard deviation of 2,400
a. what is the probability of getting more than 12,000 hits?
b. what is the probability of getting fewer than 9,000 hits?
Bhartdarshan'is an internet-based travel agency wherein customer can see videos of the cities they plan to visit. The number of hits daily is a normally distributed random variable with a mean of 10,000 and a standard deviation of 2,400.
a. What is the probability of getting more than 12,000 hits