Thread: Delta?

what does the symbol delta(the triangle symbol)x mean?

It is the 4th Greek letter and usually represents 'change in' x

so what would I do if the problem is:

(f(2+delta(x))+ f(2)) / delta(x)

the equation:x^2 - 2x + 1

The problem is most likely to find the derivative of f in the point x=2.

Originally Posted by CalcGeek31

so what would I do if the problem is:

(f(2+delta(x))+ f(2)) / delta(x)

the equation:x^2 - 2x + 1

Delta, as Galactus said, represents change in x. In your case, it represents the change of x as it approaches zero. This is the derivative at the point x = 2. Also, you made a small typo:

Im not sure I understand...

my problem is f(x) is equal to the second equation... now evaluate the first equation...

Let



Our objective here is to get rid of the h in the denominator so we can find the limit. Now, let's evaluate f(2+h) and f(2)





Now simply replace and simplify. You'll find that you can cancel the h in the denominator after all.

ohhh... now that makes perfect sense... it takes the form of f(x+h) thank you

I also have a similar problem in which there is no change in x. does this mean I work it all the way up until I do the limit?

wait... I get down to lim(h-> 0) (2h + h^2 - 2) / h
then how do I cancel the denominator?

Originally Posted by CalcGeek31

wait... I get down to lim(h-> 0) (2h + h^2 - 2) / h
then how do I cancel the denominator?

You made a mistake while simplifying:






...

ahhh... k so my final answer is 2?

Originally Posted by CalcGeek31

ahhh... k so my final answer is 2?

EDIT: Yes, I made trivial mistake. You're correct.

from that... -2(h) = -2 h + 4h

[
your +2h in here should be -2h...