Question

Question 1.1. Which relation is a function?
(Points : 4)
A {(1, 2); (2, 3); (3, 4); (1, 5)}
B {(1, 2); (1, 3); (1, 4); (1, 5)}
C {(1, 2); (2, 3); (3, 4); (2, 5)}
D {(1, 2); (2, 2); (3, 2); (4, 2)}

Answer 1

help please :)

Answer 2

For every x there must be a UNIQUE y, so if you have the second coordinate has a different value as for the same x value, it is NOT a function.

for example, (20,2) and (20,100) is NOT a function because for the same x you have two different y values.

Answer 3

soo its b ??

Answer 4

sorry im very bad at math >.<

Answer 5

2. What is the range of the relation? {(1, 2), (2, 4), (3, 2), (4, 6)}

(Points : 4)
A {1, 2, 3, 4}
B {1, 2, 3, 4, 6}
C {2, 4, 6}
D {2, 4}

Answer 6

Erm, B is a line X=1
D is a line Y=2 or F(x)=2

Answer 7

The 1st is not b, the input 1 produces 4 different y values, which is definitely NOT unique.

Answer 8

1. D
2.C

Answer 9

Why is 1 D?

Answer 10

Reasons mean you understand. Math is about thinking.

Answer 11

because it has the same values

Answer 12

The key is that the second coordinate can not be different for the same input.

For example, if you pressed a button on a candy machine and got M&Ms. Then you pressed the same button and got Snickers. That would NOT be a good function. When this happens, we say that rule is not logical. A function is just a rule, which is a relation between the input and the output. The button you press gives the same result every time.

Answer 13

That is why D is the correct answer for 1.

Answer 14

and 2 is c

Answer 15

I need to understand your thought process. Why?