question the piecewise function f(x) is graphed below. use geometric formulas to evaluate the following…

question the piecewise function f(x) is graphed below. use geometric formulas to evaluate the following definite integral. ∫₂¹² f(x) dx submit your answer as an exact value.

question the piecewise function f(x) is graphed below. use geometric formulas to evaluate the following definite integral. ∫₂¹² f(x) dx submit your answer as an exact value.

Answer

Explanation:

Step1: Divide the region

The region under the curve from $x = 2$ to $x=12$ can be divided into three geometric - shapes: a triangle from $x = 2$ to $x = 5$, a triangle from $x = 5$ to $x = 6$, and a trapezoid from $x = 6$ to $x = 12$.

Step2: Calculate the area of the first triangle

The base of the first triangle from $x = 2$ to $x = 5$ is $b_1=5 - 2=3$, and the height $h_1 = 3$. The area of a triangle is $A=\frac{1}{2}bh$. So, $A_1=\frac{1}{2}\times3\times3=\frac{9}{2}$.

Step3: Calculate the area of the second triangle

The base of the second triangle from $x = 5$ to $x = 6$ is $b_2=6 - 5 = 1$, and the height $h_2=3$. So, $A_2=\frac{1}{2}\times1\times3=\frac{3}{2}$.

Step4: Calculate the area of the trapezoid

The trapezoid from $x = 6$ to $x = 12$ has bases $b_1 = 0$ and $b_2=3$, and height $h=6$. The area of a trapezoid is $A=\frac{(b_1 + b_2)h}{2}$. So, $A_3=\frac{(0 + 3)\times6}{2}=9$. Also, since the trapezoid is below the $x$-axis, its contribution to the integral is negative, $A_3=-9$.

Step5: Sum up the areas

The definite - integral $\int_{2}^{12}f(x)dx=A_1+A_2+A_3$. Substitute the values: $\int_{2}^{12}f(x)dx=\frac{9}{2}+\frac{3}{2}-9$. First, add the first two terms: $\frac{9 + 3}{2}-9=\frac{12}{2}-9=6 - 9=-3$.

Answer:

$-3$