1. The problem presents two expressions: $36 + 39$ and $23 - 3$, and also includes integral and partial derivative notation. 2. First, evaluate the simple arithmetic expressions: - $36 + 39 = 75$ - $23 - 3 = 20$ 3. The integral expression $\int_a^b f(x)\,dx$ represents the definite integral of the function $f(x)$ from $a$ to $b$, which is a general notation and cannot be simplified without knowing $f(x)$, $a$, and $b$. 4. The partial derivative notation $\frac{\partial}{\partial x}$ indicates differentiation with respect to $x$, but no function is provided to differentiate. 5. Therefore, the evaluated results are: - $36 + 39 = 75$ - $23 - 3 = 20$ 6. The integral and partial derivative expressions remain symbolic as no further information is given.