`Ifx=int_0^y(dt)/(sqrt(1+9t^2))a n d(d^2y)/(dx^2)=a y ,t h e nfin da`

Explanation

To solve the problem step-by-step, we will start from the given integral and derive the necessary expressions to find the value of \( a \).

### Step 1: Define the integral
We are given:
\[ x = \int_0^y \frac{dt}{\sqrt{1 + 9t^2}} \]

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