Domain and Range
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domain describes the numbers that the function applies to.
range describes the values that you get from the function when using only numbers from the domain.
basically, domain is the numbers that go into the function, range is the numbers that come out of the function.
x&y intercepts (I hope you`re talking about graphs...) are the points on the x&y axis where the graph crosses them. for example, the y-intercept of the graph y=x+2 is 2.
Does this help?
range describes the values that you get from the function when using only numbers from the domain.
basically, domain is the numbers that go into the function, range is the numbers that come out of the function.
x&y intercepts (I hope you`re talking about graphs...) are the points on the x&y axis where the graph crosses them. for example, the y-intercept of the graph y=x+2 is 2.
Does this help?
Domain is the set of all values that can be input into the function to get a meaningful result, or in the case of a graph, the set of all possible x values. The range is the set of all outputs for the function, which on a graph is the set of all possible y values.
For the function f(x)=x, also known as y=x, both the domain and range include all values between positive and negative infinity.
For f(x)=1/x, the domain is everything but zero, and the range is also everything but zero.
For f(x)=x^2, the domain is all values between positive and negative infinity, and the range is all values greater than or equal to zero.
To find domain, investigate whether any inputs will give nonsensical or undefined results, and exclude those. What remains is the domain.
To find range, investigate whether there are any values that will never be output from the function, and exclude those. What remains is the range.
For intercepts, you look for where in the function either x or y will be zero. When x=0, that's the y intercept. When y=0, that's an x intercept. Note that a function can potentially have any number of x intercepts but by definition can only have one y intercept. If you're not dealing with a function, then this restriction is removed.
Hope that helps. Check out Wikipedia and Wolfram Alpha if you want further references. Good luck!
For the function f(x)=x, also known as y=x, both the domain and range include all values between positive and negative infinity.
For f(x)=1/x, the domain is everything but zero, and the range is also everything but zero.
For f(x)=x^2, the domain is all values between positive and negative infinity, and the range is all values greater than or equal to zero.
To find domain, investigate whether any inputs will give nonsensical or undefined results, and exclude those. What remains is the domain.
To find range, investigate whether there are any values that will never be output from the function, and exclude those. What remains is the range.
For intercepts, you look for where in the function either x or y will be zero. When x=0, that's the y intercept. When y=0, that's an x intercept. Note that a function can potentially have any number of x intercepts but by definition can only have one y intercept. If you're not dealing with a function, then this restriction is removed.
Hope that helps. Check out Wikipedia and Wolfram Alpha if you want further references. Good luck!
For DomainCODE-D said:
you determine what values you can use to replace x with. So with the equation y=x, every number can replace x and still have it be a true statement. But with y=squareroot(x) the domain is all positive numbers because you can't take the square root of a negative number.
Range
you do the same thing but for Y, so determine what values you will get for the output Y for any input, X. So for y=x: any number you put in the X place will yield the same output so the range is all real numbers. For y=squareroot(x), you can't take the square root of a number and get a negative number, but you can get any positive number, so the range is all positive numbers. For an example where the domain and range isn't the same: y=x^2. since any number can be squared the domain is all real numbers, however since a positive or a negative number squared is always going to positive the range is all positive numbers because you can never have a negative out put.
For x and y intercepts
X intercept you replace y with 0 and solve the equation out, so for y=5x+10 you would make it 0=5x+10 and solve it out to be x=-2 so you x intercept is -2.
Y intercept you replace x with 0 and solve out for Y so for y=5x+10 you would make it y=5(0)+10 or y=10 and that is your y intercept