How to solve a differential equation problem that contains an integral term?

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$$ y(x) = \int_{0}^{x} (y(t))^{\frac{1}{2}} dt + 1 $$

What will be a general solution? I couldn't find any related problems in stackexchange. I tried

$$u'(x) = \frac{1}{2}\int_{0}^{x} (y(t))^{\frac{1}{2}} (y ′ (t))dt $$

and

$$u''(x) = \frac{1}{4}\int_{0}^{x} y(t)^(1/2) (y ′(t))^2dt$$

But, I couldn't go further. Thanks in advance.

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From $y(x) = \int_{0}^{x} (y(t))^{\frac{1}{2}} dt + 1$ you get, by the FTC, the initial value problem

$y'(x)=(y(x))^{\frac{1}{2}}, $

$y(0)=1$.

Can you proceed ?

0
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You made a mistake when you took the derivative $$y(x) = \int_{0}^{x} (y(t))^{\frac{1}{2}} dt + 1$$ $$y'(x) =\frac {dy}{dx}=\frac {d}{dx} (\int_{0}^{x} (y(t))^{\frac{1}{2}} dt + 1)$$ And not ( which is what you did) : $$y'(x) = \frac {d}{dt}(\int_{0}^{x} (y(t))^{\frac{1}{2}} dt + 1)$$ Use the Fondamental Theorem of Calculus $$y'=(y(x))^{\frac{1}{2}}.1$$ It's an easy ode to solve...since it's separable

You will have a constant C to evaluate it use the fact that

$$y(0) = \int_{0}^{0} (y(t))^{\frac{1}{2}} dt + 1=1$$

The integral is zero..