- #1
Stephanus
- 1,316
- 104
Dear PF Forum,
I'd like to study integral.
But I just realize that I'm lack of basic integral.
Can I ask here?
Let y=x2
Here is the graph.
So,
1. dx is the distance between the red vertical lines? But it's very, very, very small distance.
2. f(x) * dx is the yellow area?
3. ##\int_0^2 x^2\,dx## is the green (plus yellow) area?
4. And one more thing. The blue line function can be derived from the derivative of f(x)?
For example the derivative of x2 is 2x. So a line that crosses (x,f(x)) where x=1 is 2.
The blue line function is y = 2x.
If it crosses (x,f(x)) where x = 2, then the blue line function is y = 4x?
Thank you very much
I'd like to study integral.
But I just realize that I'm lack of basic integral.
Can I ask here?
Let y=x2
Here is the graph.
So,
1. dx is the distance between the red vertical lines? But it's very, very, very small distance.
2. f(x) * dx is the yellow area?
3. ##\int_0^2 x^2\,dx## is the green (plus yellow) area?
4. And one more thing. The blue line function can be derived from the derivative of f(x)?
For example the derivative of x2 is 2x. So a line that crosses (x,f(x)) where x=1 is 2.
The blue line function is y = 2x.
If it crosses (x,f(x)) where x = 2, then the blue line function is y = 4x?
Thank you very much