Inner Product Space Homework: Is <f(t)|g(t)> an Inner Product?

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SUMMARY

The discussion centers on determining whether the expression = ∫₀¹ f'(t)g'(t) + f(0)g(0) qualifies as an inner product space for real functions with continuous derivatives. The user successfully demonstrated that the first three conditions of linearity and symmetry are satisfied. The final condition, ≥ 0, was confirmed to hold true, as the integral ∫₀¹ [f'(t)]² + f(0)² is non-negative due to the square integrability of continuous functions and their derivatives.

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NeedPhysHelp8
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Homework Statement



Is the following an inner product space if the functions are real and their derivatives are continuous:

&lt;f(t)|g(t)&gt; = \int_0^1 f&#039;(t)g&#039;(t) + f(0)g(0)


Homework Equations



I was able to prove that it does satisfy the first 3 conditions of linearity and that
&lt;f(t)|g(t)&gt; = &lt;g(t)|f(t)&gt;
But I was struggling with the last condition that:
&lt;f(t)|f(t)&gt; \geq 0


The Attempt at a Solution


I was able to get the following:
&lt;f(t)|f(t)&gt; = \int_0^1 [f&#039;(t)]^2 + f(0)^2
Since this is square integrable, I figure that it must be greater than or equal to zero if the functions and their derivatives are continuous.
Am I right? It's the last term that's giving me some trouble.
Thanks!
 
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NeedPhysHelp8 said:
I was able to get the following:
&lt;f(t)|f(t)&gt; = \int_0^1 [f&#039;(t)]^2 + f(0)^2
Since this is square integrable, I figure that it must be greater than or equal to zero if the functions and their derivatives are continuous.
Am I right? It's the last term that's giving me some trouble.
Thanks!

Everything you have written down is non-negative. So, yes, you are correct.
 

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