The anti derivative of (sin2x - 4e3x) is the function of x whose derivative is (sin2x - 4e3x) .
It is known that,
\(\frac{d}{dX}\bigg(-\frac{1}{2}cos2x-\frac{4}{3}e^{3x}\bigg) = \sin2x-4e^{3x}\)
Therefore, the anti derivative of (sin2x - 4e3x) is\(\bigg(-\frac{1}{2}cos2x-\frac{4}{3}e^{3x}\bigg) \) .
Let \( f : (0, \infty) \to \mathbb{R} \) be a twice differentiable function. If for some \( a \neq 0 \), } \[ \int_0^a f(x) \, dx = f(a), \quad f(1) = 1, \quad f(16) = \frac{1}{8}, \quad \text{then } 16 - f^{-1}\left( \frac{1}{16} \right) \text{ is equal to:}\]

The representation of the area of a region under a curve is called to be as integral. The actual value of an integral can be acquired (approximately) by drawing rectangles.
Also, F(x) is known to be a Newton-Leibnitz integral or antiderivative or primitive of a function f(x) on an interval I.
F'(x) = f(x)
For every value of x = I.
Integral calculus helps to resolve two major types of problems: