We can solve the integral $\int\left(x+1\right)\left(x-4\right)dx$ by applying integration by parts method to calculate the integral of the product of two functions, using the following formula
$\displaystyle\int u\cdot dv=u\cdot v-\int v \cdot du$
The integral of a constant is equal to the constant times the integral's variable
$\int xdx-4x$
7
Applying the power rule for integration, $\displaystyle\int x^n dx=\frac{x^{n+1}}{n+1}$, where $n$ represents a number or constant function, in this case $n=1$
$\frac{1}{2}x^2-4x$
Intermediate steps
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Now replace the values of $u$, $du$ and $v$ in the last formula
Solving a math problem using different methods is important because it enhances understanding, encourages critical thinking, allows for multiple solutions, and develops problem-solving strategies. Read more
Integration assigns numbers to functions in a way that can describe displacement, area, volume, and other concepts that arise by combining infinitesimal data.