SOLUTION: which of these sets represents a function?.. (2,-2,), (3, -2), (2,3) or (9,pie), (5,7), (4,pie) or both or neither PS: When I say pie I

Question 142821: which of these sets represents a function?..

(2,-2,), (3, -2), (2,3) or

(9,pie), (5,7), (4,pie) or

both or neither

PS: When I say pie I mean the 3.14 sign thing...
Answer by nabla(475) (Show Source): You can put this solution on YOUR website!
Functions must pass the vertical line test, which is to say that they must not be multi-valued per x. Thus, having points sharing x coordinates with different y coordinates is a no-no.
Your answer is, from the reasoning I have supplied, the first choice (2,-2,), (3, -2), (2,3) because x=2 is multi-valued. For a counter-example, consider the simple graph of f(x)=x^2. This is obviously a function. But, as you can see by the graph, different x values take on the same y values (namely, their opposites):
(-2)^2=2^2=4

By the way, pi is probably the most important mathematical constant there is. It represents the ratio of a circle's circumference to its diameter. That is, how long it is around over how wide it is. For future mathematical applications it's probably best to memorize it to, say, 5 decimal places. pi=3.14159 26535 89793 23846 26433 83279 50288 41971 69399 37510...
RELATED QUESTIONS
Which of these sets represents a function: a) (2,-2), (3,-2), (2,3) b) (9,pi), (5,7),... (answered by vleith)

Which of these sets represents a function, [(-1, 8), (5,7),(5rr)] [(7,3),(5,-2),(4,3)] (answered by MathLover1)

Find cosx/2, given cot x=(-3), with sign of pie/2 < x < sign of pie Here is what I... (answered by Theo)

what are the trig function values of cot x= -8/15 and 3 pie/2 greater than or equal to x... (answered by lwsshak3)

Which of these sets represents a function, [(-1,8),5,7), (5,rr)] (rr =... (answered by Alan3354)

tan (5 pie/9) - cot (3 pie/2) =... (answered by stanbon)

without using calculater note: pie=3.14 1.sin of... (answered by KMST)

FInd the exact value of tan(A-B) if cos(A)=3/5 where 0< or equal to A (answered by lwsshak3)
what is the period of the following function? y=2tan(3x-pie/2) 1. 1 2. pie 3 pie/3... (answered by Alan3354)