The angle θ 1 is located in Quadrant IV, and cos ⁡ ( θ 1 ) = 9/ 19 , theta, start subscript, 1, end subscript, right parenthesis, equals, start fraction, 9, divided by, 19, end fraction . What is the value of sin ⁡ ( θ 1 ) sin(θ 1 )sine, left parenthesis, theta, start subscript, 1, end subscript, right parenthesis? Express your answer exactly.

Step-by-step explanation:

We are given that is in fourth quadrant.

is always positive in 4th quadrant and  

is always negative in 4th quadrant.

Also, we know the following identity about and :

Using \theta_1 in place of \theta:

We are given that

is in 4th quadrant so is negative.

So, value of

if you are saying purchasing 3 social media ads and one newspaper ad counts as one purchase then there are:

6 purchases

if you are asking how many of each then:

18 social media ads

6 newspaper ads