Domain and Range (1 Viewer)

[Maddy]

I'm confused about how to find the domain and range of a function. We learnt it last year and I have completely forgotten!! Any tips??

 

[Lazarus]

domain = all possible x-values the function can take
range = all possible y-values the function can take

e.g. for y = x²

domain: all real x
range: y >= 0

 

[iambored]

i normally look at the equation they give you, and figure out what can and can't go in there, and then what y can and can't be.

for example in a fraction, if the bottom of the fraction is (x-3) then x doesnt equal 3 as then there will be a 0 at the bottom of the fraction which isn't allowed. some just take a bit of logical thinking

sometimes you can test numbers if you are really confused

 

[Maddy]

Ohh ok! thank you!!!

 

[RX8LP]

I think the best way 2 make sure ure getting the correct answer for a domain/range question is 2 quicly draw up da function (if it can be possible). This way u can clearly see the range of y values and x values.