can someone please tell me what the horizontal line test is used for...I can't find the info anywhere

Question

jim_thompson5910 · Answer

it's used to see if a function is one-to-one

jim_thompson5910 · Answer

if a function is one-to-one, then it is invertible (ie it has an inverse)

anonymous · Answer

ok so how does it work...I'm looking at a graph with the line sitting directly on the 0, it curves up, so what does this mean?

jim_thompson5910 · Answer

can you post the picture of it?

anonymous · Answer

@jim_thompson5910, posted a link

jim_thompson5910 · Answer

this function is NOT one-to-one because it fails the horizontal line test

you can pass a horizontal line through it and it will pass through more than one point, so it fails the test

anonymous · Answer

ohhh ok, so if the line passes through more than one point it fails the test...thank you so much

jim_thompson5910 · Answer

yep, yw

anonymous · Answer

can you tell me how to simplify the expressiong log 0.1?