Answer:
Exponential decay.
Step-by-step explanation:
You can use a graphing utility to check this pretty quickly, but you can also look at the equation and get the answer. Since the function has a variable in the exponent, it definitely won't be a linear equation. Quadratic equations are ones of the form ax^2 + bx + c, and your function doesn't look like that, so already you've ruled out two answers.
From the start, since we have a variable in the exponent, we can recognize that it's exponential. Figuring out growth or decay is a little more complicated. Having a negative sign out front can flip the graph; having a negative sign in the exponent flips the graph, too. In your case, you have no negatives; just 2(1/2)^x. What you need to note here, and you could use a few test points to check, is that as x gets bigger, (1/2) will get smaller and smaller. Think about it. When x = 0, 2(1/2)^0 simplifies to just 2. When x = 1, 2(1/2)^1 simplifies to 1. Already, we can tell that this graph is declining, but if you want to make sure, try a really big value for x, like 100. 2(1/2)^100 is a value very very very veeery close to 0. Therefore, you can tell that as the exponent gets larger, the value of the function goes down and gets closer and closer to zero. This means that it can't be exponential growth. In the case of exponential growth, as the exponent gets bigger, your output should increase, too.
Answer:
There you go.
Step-by-step explanation:
Please do tell me if it's wrong.
Answer: C
Step-by-step explanation:
Answer:
0.58 = 58% probability she passes both courses
Step-by-step explanation:
We can solve this question treating the probabilities as a Venn set.
I am going to say that:
Event A: She passes the first course.
Event B: She passes the second course.
The probability she passes the first course is 0.67.
This means that 
The probability she passes the second course is 0.7.
This means that 
The probability she passes at least one of the courses is 0.79.
This means that 
a. What is the probability she passes both courses
This is 
.
We use the following relation:
So
0.58 = 58% probability she passes both courses
