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temp
Sep7-07, 04:43 AM
hello
commonly we have:
\int^t_0 \ dx=M

"M" is a specific number (the result of integal)

my question:
having value of "M", how we can find the "t" value

VietDao29
Sep7-07, 05:27 AM
hello
commonly we have:
\int^t_0 \ dx=M

"M" is a specific number (the result of integal)

my question:
having value of "M", how we can find the "t" value

This sounds much like homework to me. >"<

What have you done? Have you tried anything?

Ok, I'll give you some hints then:

1. What is the anti-derivative of: \int dx = ?

2. What is : \int_0 ^ t dx = ? in terms of t?

3. What is the relation between t, and M?

cristo
Sep7-07, 06:00 AM
hello
commonly we have:
\int^t_0 \ dx=M

"M" is a specific number (the result of integal)

my question:
having value of "M", how we can find the "t" value

In case this isn't homework and is a question from curiosity: In general, there is a function being integrated; \int^t_0 f(x) dx=M. In which case, the answer to your question is "only if we know the function, f."

temp
Sep7-07, 06:31 AM
i know the function f(x)
suppose that f(x) is x

\int^t_0 x dx=M

HallsofIvy
Sep7-07, 07:18 AM
What IS the integral (anti-derivative) of x? Do the integration on the left, set it equal to M and solve the equation for t.

In the very simple case, you started with, \int_0^t dx, the anti-derivative of the constant 1 is just x
\int_0^t dx= x\right|_0^t= t[/itex]
In that case, whatever number M is, you have t= M. For the case of
[tex]\int_0^t x dx= M
it is almost as simple.