A graph is a function if any vertical line intersects it at most once.
In simple terms, if a vertical line meets a graph in more than one place it is not a function.
The Vertical Line Test An example might be x=cos(y). At any value of x between -1 a nd +1 (a vertical line on the graph) this is multivalued (and so it is called "multivalued"). The relation is a function, because given y you can calculate x. x is a function of y. The relation between y and x can also be written y=cos-1(x) "y is the angle whose cosine is x". From that point of view you can say " y is not a function of x" because for each x, there is more than one y that satisfyies the equation. To summarize, in this example x is a function of y but y is not a function of x.
They mean the graph/function is decreasing.
A graph is a representation of a thing/system, and can be used to test a hypothesis. For example, if you have a graph of a trend you can find the function of that trend. Then, you can plug in values the graph defines--say, at 2 the graph reaches 5--and if the function works, you know you have modeled the phenomenon correctly. This function testing can work to test a hypothesis, especially in finding trends.
A graph is a function if any vertical line intersects it at most once.
In simple terms, if a vertical line meets a graph in more than one place it is not a function.
The Vertical Line Test An example might be x=cos(y). At any value of x between -1 a nd +1 (a vertical line on the graph) this is multivalued (and so it is called "multivalued"). The relation is a function, because given y you can calculate x. x is a function of y. The relation between y and x can also be written y=cos-1(x) "y is the angle whose cosine is x". From that point of view you can say " y is not a function of x" because for each x, there is more than one y that satisfyies the equation. To summarize, in this example x is a function of y but y is not a function of x.
They mean the graph/function is decreasing.
A function takes one input and assigns to it exactly one output, so a graph qualifies as a function if it passes the vertical line test (run a vertical line across the entire plane; the function should only cross your line once no matter where you are testing).
A graph is a representation of a thing/system, and can be used to test a hypothesis. For example, if you have a graph of a trend you can find the function of that trend. Then, you can plug in values the graph defines--say, at 2 the graph reaches 5--and if the function works, you know you have modeled the phenomenon correctly. This function testing can work to test a hypothesis, especially in finding trends.
A relation is a function if every value in the domain is mapped to only one value in the range. A non-mathematical example is mothers. Leaving aside surrogacy, every person has only one mother. Therefore the relation f(x) = x's mother is a function. But f(x) = x's ancestor is not a function because everyone has loads of ancestors. They may not all be known but that is not relevant.
A graph that has isolated points is discontinues if isolated means that a point is plotted say a but the limit as f(x) approaches a does not equal a
When it doesn't fulfill the requirements of a function. A function must have EXACTLY ONE value of one of the variables (the "dependent variable") for every value of the other variable or variables (the "independent variable").
When it doesn't fulfill the requirements of a function. A function must have EXACTLY ONE value of one of the variables (the "dependent variable") for every value of the other variable or variables (the "independent variable").
the graph of cos(x)=1 when x=0the graph of sin(x)=0 when x=0.But that only tells part of the story. The two graphs are out of sync by pi/2 radians (or 90°; also referred to as 1/4 wavelength or 1/4 cycle). One cycle is 2*pi radians (the distance for the graph to get back where it started and repeat itself.The cosine graph is 'ahead' (leads) of the sine graph by 1/4 cycle. Or you can say that the sine graph lags the cosine graph by 1/4 cycle.
When it doesn't fulfill the requirements of a function. A function must have EXACTLY ONE value of one of the variables (the "dependent variable") for every value of the other variable or variables (the "independent variable").