Functions

[Stardust1]

How do I solve this?

 

[Stardust1]

I keep getting x(2x +4h + 1)/h but the answer states 4h+2x+1.

 

[blamocur]

I keep getting x(2x +4h + 1)/h but the answer states 4h+2x+1.

Can you show us how you are getting your answer?
Thanks.

 

[Stardust1]

 

[blamocur]

I get the same answer as you. I suspect that there is a typo in your book (-f(x) instead of -f(h)):
[math]\frac{f(x+h)-f(\mathbf x)}{h} = 4x + 2h + 1[/math]Note that the answer is also slightly different from the one you posted.

 

[Stardust1]

Oh, so it must be a typo? I was very confused about this question. Thank you for clearing my doubt!

 

[Dr.Peterson]

I get the same answer as you. I suspect that there is a typo in your book (-f(x) instead of -f(h)):
[math]\frac{f(x+h)-f(\mathbf x)}{h} = 4x + 2h + 1[/math]Note that the answer is also slightly different from the one you posted.

Or they divided by x rather than h. that gives their answer.