- #1

intenzxboi

- 98

- 0

i know for a equation to be 1-1 they have to pass the horizontal line test.

so say for example

(-8 + x) ^4

i know this is not a one to one because it gives me a parabola.

The problem that I am having is being able to explain in a equation.

MY SOLUTION

First derive the equation so that i know where it is increasing/decreasing

4(-8+x)^3

so i take -8+x>0 is increasing

x>8 <----- I am sure that's correctnow to find it decreasing you flip the sign

and i take -8+x<0 is decreasing?

but then i also get x<8

What I'm i doing wrong??So if I am doing this right then that means that for a function to be one to one.. It either has to be increasing OR decreasing?? but cannot be both?

so say for example

(-8 + x) ^4

i know this is not a one to one because it gives me a parabola.

The problem that I am having is being able to explain in a equation.

MY SOLUTION

First derive the equation so that i know where it is increasing/decreasing

4(-8+x)^3

so i take -8+x>0 is increasing

x>8 <----- I am sure that's correctnow to find it decreasing you flip the sign

and i take -8+x<0 is decreasing?

but then i also get x<8

What I'm i doing wrong??So if I am doing this right then that means that for a function to be one to one.. It either has to be increasing OR decreasing?? but cannot be both?

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